Water repellency-imparting fiber article

ABSTRACT

A water repellency-imparted fiber article (10) of the present invention includes: a fiber article (1) having a skin-facing surface (1a) and a non-skin-facing surface (1b); and a water repellency-imparting agent attached to the fiber article (1). The fiber article (1) contains a water-absorbent fiber and has water absorbency in terms of a water absorption time of 30 seconds or less as measured in accordance with the dropping method of JIS L-1907. The water repellency-imparted fiber article (10) has a non-skin-side water-repellent region (2) on the non-skin-facing surface (1b) of the fiber article (1), the non-skin-side water-repellent region (2) including a portion to which the water repellency-imparting agent is attached. The water repellency-imparted fiber article (10) has a water absorbing layer (11) in a section of the fiber article that overlaps the non-skin-side water-repellent region (2) in a plan view and on a side that is closer to the skin of a user than the non-skin-side water-repellent region (2), the water absorbing layer maintaining the water absorbency. A surface of the non-skin-side water-repellent region 2 has a water contact angle of 80 degrees or greater and a water absorption rate of 10 seconds or greater.

TECHNICAL FIELD

The present invention relates to water repellency-imparted fiberarticles obtained by applying water-repellent treatment to fiberarticles, such as various items of clothing and incontinence pads, whichare to be put on the skin when use.

BACKGROUND ART

Inner clothing typified by underwear is a typical example of a fiberarticle that is made mainly of fibers and is to be directly put on theskin when use. Also, a type of absorbent article is known which isattached to the inner side of underwear or the inner side of a diaper ora diaper cover and primarily absorbs urine. Such absorbent articles arealso a kind of fiber article. Patent Literature 1 discloses, as a kindof such absorbent article, a male incontinence pad having a structure(leak-proof cuff) that stops a lateral flow of excreted urine so as toprevent urine from leaking out even if a large amount of urine isexcreted at one time. It is required, for example, that a fiber articlelike this absorb a bodily fluid excreted from the body, such as sweat,urine, or blood, and be free from a wet feel and a sticky feel on asurface thereof that is in contact with the skin.

Patent Literature 2 discloses, as a fabric cloth that is free from asticky feel even if a wearer wearing the fabric cloth sweats heavily, afabric cloth having, in the surface thereof, a water-repellent sea(matrix) and a plurality of water-absorbent island (domains) therein,the area per single island and the ratio of the total area of theislands to the area of that surface being within respective specificranges. The fabric cloth disclosed in Patent Literature 2 is produced bycarrying out textile printing on the surface of a water-absorbent fabriccloth according to a known method, such as rotary screen printing, usingvarious water repellents, such as fluorine or silicone water repellents.

Patent Literature 3 discloses that a woven or knitted fabric that isless likely to cause a wet feel and also has moisture absorbency can beobtained by subjecting a woven or knitted fabric containing a cottonfiber to alkali treatment to thereby remove cotton wax contained in thecotton fiber, and thereafter partially applying a water repellent to atleast one of the front and back sides of the woven or knitted fabric. InPatent Literature 3, there is a description to the effect that the waterrepellent is preferably applied to only one side of the woven or knittedfabric that comes into contact with the skin, and that the applicationpattern of the water repellent is preferably a lattice pattern or apattern such that polygons are successively arranged while sharingcorners with each other.

Patent Literature 4 discloses, as a fabric cloth for preventing sweatstains that are caused as a result of sweating, a sweat-stain preventingfabric cloth made of a polyester fiber, wherein a water repellent isapplied only the surface on one side of the fabric cloth while thesurface on the other side has an uneven structure. The sweat-stainpreventing fabric cloth disclosed in Patent Literature 4 is disposedwhen use such that the surface to which the water repellent is appliedis arranged on an ambient air-side, and that the other surface, whichhas the uneven structure, is arranged on the skin side. In PatentLiterature 4, there is a description to the effect that since thesurface that comes into contact with the skin during use has the unevenstructure, the area of contact between the skin and the fabric clothdecreases, resulting in a reduced sticky feel, and also that since sweatis diffused along depressions of the uneven structure, the drying rateincreases, resulting in an enhancement in the sweat-stain preventingeffect. Moreover, with regard to the water repellent, in PatentLiterature 4, there is a description to the effect that applying thewater repellent to the entire surface of the fabric cloth is preferablecompared to applying it partially to the surface, in view of obtainingan excellent sweat-stain preventing effect.

Patent Literature 5 discloses a fluorochemical composition that canimpart, to a fiber article, resistance against soil and stains caused bya bodily fluid such as sweat, or more specifically, oil repellency,water repellency, stain-release properties, stain resistance, and otherproperties. In Patent Literature 5, there is a description to the effectthat, when this fluorochemical composition is applied to a fiber articleto thereby form a coating thereon, the coating can be maintained evenafter the fiber article is washed a plurality of times.

CITATION LIST Patent Literature

Patent Literature 1: JP 2015-188714A

Patent Literature 2: JP 2012-126036A

Patent Literature 3: JP 2007-162150A

Patent Literature 4: JP 2011-226001A

Patent Literature 5: JP 2010-529263A

SUMMARY OF INVENTION

The present invention provides a water repellency-imparted fiber articleincluding: a fiber article having a skin-facing surface to be disposedon a side that is relatively close to the skin of a user during use anda non-skin-facing surface to be disposed on a side that is relativelyaway from the skin of the user, the fiber article containing awater-absorbent fiber and having water absorbency in terms of a waterabsorption time of 30 seconds or less as measured in accordance with thedropping method of JIS L-1907; and a water repellency-imparting agentattached to the fiber article.

The water repellency-imparted fiber article has a non-skin-sidewater-repellent region on the non-skin-facing surface of the fiberarticle, the non-skin-side water-repellent region including a portion towhich the water repellency-imparting agent is attached.

The water repellency-imparted fiber article has a water absorbing layerin a section of the fiber article that overlaps the non-skin-sidewater-repellent region in a plan view and on a side that is closer tothe skin of the user than the non-skin-side water-repellent region, thewater absorbing layer maintaining the water absorbency.

A surface of the non-skin-side water-repellent region has a watercontact angle of 80 degrees or greater and a water absorption rate of 10seconds or greater.

Also, the present invention provides a method for producing the waterrepellency-imparted fiber article of the present invention, the methodincluding applying a water repellency-imparting agent to anon-skin-facing surface of a fiber article having water absorbency interms of a water absorption time of 30 seconds or less as measured inaccordance with the dropping method of JIS L-1907.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a schematic view of a pair of water repellency-impartedunderpants, which is a piece of inner clothing, of an embodiment of awater repellency-imparted fiber article of the present invention, and itshows a state in which the water repellency-imparted underpants is worn.

FIG. 2 is another schematic view of the water repellency-impartedunderpants shown in FIG. 1, and it shows a state in which a pair oftrousers, which is a piece of outer clothing, is worn on the underpants.

FIG. 3 is a schematic cross-sectional view of another embodiment of thewater repellency-imparted fiber article of the present invention takenalong a thickness direction thereof, and it shows a state in which thewater repellency-imparted fiber article is used in combination with apiece of outer clothing.

FIG. 4(a) is a microscope photograph of a non-skin-side water-repellentregion of a specific example of the water repellency-imparted fiberarticle of the present invention, and FIG. 4(b) is a microscopephotograph of the opposite side to the side on which the non-skin-sidewater-repellent region shown in FIG. 4(a) is formed, that is, askin-facing surface of the specific example.

FIG. 5 is an EDS image obtained by imaging, with an energy dispersiveX-ray spectrometer (EDS), a cross section of a specific example of thewater repellency-imparted fiber article of the present invention takenalong the thickness direction thereof.

FIG. 6 is an EDS image of the specific example of the waterrepellency-imparted fiber article shown in FIG. 5 after washing, and itshows a state in which a water repellency-imparting agent has beenremoved through washing so that a non-skin-side water-repellent regionhas disappeared.

DESCRIPTION OF EMBODIMENTS

It is a distress to some people, particularly men, that urine is notcompletely expelled during urination, and that a small amount of urineleaks after urination, soiling their underpants. In particular, in oldermen, such a distress is more serious because of the following: due tourethral dilation or the like that accompanies aging, urine is morelikely to remain in the urethra after urination, and the residual urinemay be accidentally discharged from the penis, soiling the underpants.Such leakage of residual urine in the urethra is in an amount of aboutseveral to 10 mL, and often is so-called “after-dribble”, which is asmall amount, specifically about 1 mL or less, of urine leaks. Unlikeincontinence, so-called “wetting”, in which the underpants get wetthrough, such after-dribble does not necessarily require a changing ofunderpants, and partly because of this, some people do not regard suchurine leakage as a problem that needs to be immediately solved. However,after-dribble may cause an unpleasant feeling due to wet underpants, andthere also are cases where urine seeps even into outer clothing such astrousers, that is worn on inner clothing such as underpants, to soil theouter clothing, or where the odor diffuses into the surroundings. Thus,many people desire to find a countermeasure against these problems.

An example of a method for solving such problems arising fromafter-dribble, such as soiling clothes and causing odor, is use of amale incontinence pad such as that disclosed in Patent Literature 1. Asfor male incontinence pads, smaller pads for light incontinence, and thelike have also been proposed in recent years that are intended to makeit unlikely that other people notice that such a pad is worn. However,most men are reluctant to use an incontinence pad to deal with merely asmall amount of urine leakage, such as after-dribble, and actually thereis strong demand for solving the problems arising from after-dribblewithout needing to use an incontinence pad.

Moreover, although the techniques disclosed in Patent Literatures 2 and3 increase the dry feel of a surface of a fiber article that comes intocontact with the skin by applying a water repellent to that surface ofthe fiber article, the above-described soiling of clothes caused byafter-dribble is left out of consideration, and these techniques areinsufficient to deal with after-dribble. The sweat-stain preventingfabric cloth disclosed in Patent Literature 4 is effective to a certainextent in preventing sweat stains; however there is concern that airpermeability will decrease, particularly due to a configuration in whichthe water repellent is attached to the entire surface of the fabriccloth, and, for example, when the fabric cloth is used as a constituentmember of a wearable article, the fabric cloth may cause odor and skinproblems such as dampness and rashes. Also, since the sweat-stainpreventing fabric cloth disclosed in Patent Literature 4 is made ofpolyester fibers, the fabric cloth itself has poor water absorbency, andin terms of the wearing comfort as well, the fabric cloth is inferior tothose made of water-absorbent fibers such as a natural cellulose fiber.Furthermore, if the fluorochemical composition disclosed in PatentLiterature 5 is applied to a fiber article, such as underpants, tothereby make a portion of the fiber article hydrophobic, this may beeffective in preventing soiling of clothes caused by after-dribble, butthere is a risk that the fiber article will become excessivelywater-repellent, which results in that the water absorbency,flexibility, air permeability, and the like intrinsic to the fiberarticle may be reduced.

As described above, it is a distress to many people that a bodily fluid,such as a relatively small amount of urine or sweat, seeps into clothes,but the use of dedicated goods, such as incontinence pads and underarmpads, for dealing with this problem tends to be avoided. A technique hasnot yet been provided that can solve the above-described problems whileusing commonly-used clothing, such as underwear, as-is, without needingto use such dedicated goods.

Therefore, the present invention relates to providing a waterrepellency-imparted fiber article that can effectively prevent a bodilyfluid excreted from the body from seeping into the clothing and thusbecoming externally visible.

Hereinafter, the present invention will be described in detail. FIG. 1is a schematic view of a pair of water repellency-imparted underpants10, which is an embodiment of a water repellency-imparted fiber articleof the present invention, when worn, and FIG. 2 is a schematic viewshowing a state in which a pair of trousers 20, which is a piece ofouter clothing, is worn on the water repellency-imparted underpants 10.The pair of water repellency-imparted underpants 10 includes a pair ofunderpants 1, which is a fiber article (fiber article that has not yetbeen subjected to water repellency-imparting treatment) according to thepresent invention, as well as a water repellency-imparting agent(non-skin-side water-repellent region 2) attached to the underpants 1.

The underpants 1, which are an embodiment of the fiber article accordingto the present invention, are basically configured in the same manner asin common trunks-type underpants for men, which are pieces of innerclothing, and have a front body portion, a back body portion, and acrotch portion located therebetween, as well as a waist opening and apair of leg openings. The underpants 1 are so-called front-closed-typetrunks with no front opening, and a waist end portion thereof thatdefines the waist opening is elasticized by, for example, disposing afilamentous elastic member therein. The underpants 1 have a skin-facingsurface 1 a to be disposed on a side that is relatively close to theskin of a user during use, and a non-skin-facing surface 1 b to bedisposed on a side that is relatively away from the skin of the user.When the underpants 1 are worn as shown in FIG. 2, the skin-facingsurface 1 a is in contact with the skin of a wearer 100 of theunderpants, and the non-skin-facing surface 1 b is in contact with thetrousers 20. The underpants 1 constitute the main body of the waterrepellency-imparted underpants 10, and the appearance, texture, wearingcomfort, and the like of the water repellency-imparted underpants 10 arebasically derived from the intrinsic performance of the underpants 1that is the base of the water repellency-imparted underpants 10.

There is no particular limitation on the fiber article, which is thebase of the water repellency-imparted fiber article of the presentinvention, and in the cases where underpants are concerned, not onlytrunks-type underpants, such as those shown in FIGS. 1 and 2, in whichthe front body portion has a single-layer structure, but also, forexample, so called briefs-type underpants in which the front bodyportion has a double structure can be used. In the case where the frontbody portion of the underpants 1 has such a multilayer structure, asurface (outer surface) of the outermost layer, of that multilayerstructure, that is the farthest away from the skin of the wearer is thenon-skin-facing surface 1 b that comes into contact with the trousers20. This concept of the skin-facing surface and the non-skin-facingsurface with respect to the fiber article having a multilayer structureapplies to fiber articles other than underpants.

The underpants 1, which are the fiber article that is the base of thewater repellency-imparted underpants 10 serving as the waterrepellency-imparted fiber article, will be described in greater detail.The underpants 1 include a fiber sheet 11 that is made mainly of fibersincluding a water-absorbent fiber. The fiber sheet 11 constitutes themain body of the underpants 1, and the front body portion, the back bodyportion, and the crotch portion of the underpants 1 are formed by thefiber sheet 11. The skin-facing surface 1 a of the underpants 1 is theskin-facing surface of the fiber sheet 11, and the non-skin-facingsurface 1 b of the underpants 1 is the non-skin-facing surface of thefiber sheet 11. The following description regarding the fiber sheet 11applies to the underpants 1 (fiber article) as is, unless otherwisespecified.

The fiber sheet 11 is made mainly of fibers including a water-absorbentfiber. The fiber content in the fiber sheet 11 is preferably 50 mass %or greater, or more preferably 70 mass % or greater, or may also be 100mass %, that is, the fiber sheet 11 may consist of fibers. Fibers thatare usually used in various fiber products including clothing can beused as the constituent fibers of the fiber sheet 11 without limitation.Any of natural fibers and chemical fibers may be used, and the fibersmay be used singly or in combinations of two or more thereof.

The natural fibers may be plant fibers or animal fibers. Examples of theplant fibers include wood pulp such as softwood pulp and hardwood pulp,as well as non-wood fibers such as cotton and hemp. Examples of theanimal fibers include silk and wool.

Examples of the chemical fibers include synthetic fibers made of resins,such as polyester fibers, acrylic fibers, modacrylic fibers, nylonfibers, vinylon fibers, polypropylene fibers, polyvinylchloride fibers,polyethylene fibers, vinylidene fibers, and polyurethane fibers;regenerated fibers such as rayon, polynosic, cupra, and Lyocell;semisynthetic fibers such as acetate and triacetate; and inorganicfibers such as glass fibers, metallic fibers, and carbon fibers.

The fiber sheet 11 contains a water-absorbent fiber. In the presentinvention, a “water-absorbent fiber” literally refers to a fiber thathas water absorbency, or more specifically, a fiber that has an officialmoisture regain of 5% or greater. The water-absorbent fiber may be afiber that intrinsically has water absorbency, or may be a fiber that isobtained by processing a fiber that intrinsically does not have waterabsorbency to impart water absorbency thereto. The above-describednatural fibers, as well as the regenerated fibers and the semisyntheticfibers of the above-described chemical fibers can be used as thewater-absorbent fiber in the present invention.

Moreover, examples of the synthetic fibers that can be used as thewater-absorbent fiber in the present invention include intrinsicallyhydrophilic synthetic fibers, such as polyvinyl alcohol fibers andpolyacrylonitrile fibers; and fibers (hydrophilized fibers) obtained bysubjecting intrinsically hydrophobic synthetic fibers, such aspolyethylene terephthalate fibers, polyethylene fibers, polypropylenefibers, and polyester fibers, to hydrophilization treatment. Examples ofthe hydrophilized fibers include synthetic fibers into which ahydrophilizing agent is incorporated, synthetic fibers with ahydrophilizing agent attached to a surface thereof, and synthetic fiberssubjected to plasma treatment. There is no particular limitation on thehydrophilizing agent, as long as the hydrophilizing agent is a commonhydrophilizing agent for use in various fiber products includingclothing. The synthetic fiber may be a single-component fiber made of asingle type of synthetic resin or a polymer blend of two or more typesof synthetic resins, or may be a composite fiber. As used herein, thecomposite fiber refer to a synthetic fiber which is obtained bycombining two or more types of synthetic resins having differentcomponents in a spinneret and simultaneously spinning these syntheticresins therethrough, and in which the plurality of componentsindividually extending continuously in a fiber length direction adhereto one another within each single fiber. The form of the compositefibers may be, but not limited to, a core-sheath type, a side-by-sidetype, or the like.

The form of the fiber sheet 11 is not limited, and may be, for example,a woven fabric (woven cloth), a knitted fabric, a nonwoven fabric, orpaper. In the case where the fiber sheet 11 is a woven fabric or aknitted fabric, there is no particular limitation on the weave or theknitting pattern. Examples of the woven fabric include woven fabricswoven in a plain weave, a twill weave, a satin weave, or the like.Examples of the knitted fabric include weft-knitted fabrics such as flatknits, rib knits, purl knits, and interlock knits; and warp-knittedfabrics such as single tricot knits, single cord knits, half tricotknits, plain tricot knits, and queens cord knits. Examples of thenonwoven fabric include through-air bonded nonwoven fabrics, spunbondednonwoven fabrics, spunlaced nonwoven fabrics, meltblown nonwovenfabrics, resin-bonded nonwoven fabrics, and needlepunched nonwovenfabrics.

The fiber sheet 11 may have a single-layer structure, or a laminatedstructure in which a plurality of sheets having a single-layer structureare laminated. Examples of the nonwoven fabric having a laminatedstructure include a spunbonded-spunbonded laminated nonwoven fabric (SSnonwoven fabric), a spunbonded-spunbonded-spunbonded laminated nonwovenfabric (SSS nonwoven fabric), a spunbonded-meltblown-spunbondedlaminated nonwoven fabric (SMS nonwoven fabric), and aspunbonded-meltblown-meltblown-spunbonded nonwoven fabric (SMMS nonwovenfabric).

The fiber sheet 11 has water absorbency in terms of a water absorptiontime of 30 seconds or less, preferably 20 seconds or less, or morepreferably 15 seconds or less as measured in accordance with thedropping method of JIS L-1907. The water repellency-imparted underpants10 (underpants 1) include the fiber sheet 11 having the above-describedwater absorbency, and therefore can absorb water and various aqueousliquids. For example, the water repellency-imparted underpants 10(underpants 1) can absorb sweat, urine, and blood as bodily fluidsexcreted from the body.

In view of securing the above-described water absorbency of the fibersheet 11, the fiber sheet 11 preferably contains the water-absorbentfiber in a certain amount or greater. Specifically, the percentage (theoccupancy ratio) of the water-absorbent fiber to all the constituentfibers of the fiber sheet 11 is preferably 50 mass % or greater, or morepreferably 70 mass % or greater, or may also be 100 mass %, that is, allof the constituent fibers may be water-absorbent fibers.

The fiber sheet 11 may contain both a natural fiber and a syntheticfiber as its constituent fibers. As used herein, the synthetic fiberencompasses both a water-absorbent fiber and a fiber that is notwater-absorbent (non-water-absorbent fiber). A feature of the fibersheet 11 having such a mixed form of a natural fiber and a syntheticfiber is that dimensional shrinkage and shape collapse during wettingand after repeated wetting and drying (after repeated use) are lesslikely to occur. In view of enhancing such a feature of the mixed formof a natural fiber and a synthetic fiber, the mass ratio between thenatural fiber and the synthetic fiber contained in the fiber sheet 11having the mixed form, natural fiber/synthetic fiber, is preferably 1/9to 9/1, and more preferably 2/8 to 8/2.

Alternatively, the fiber sheet 11 may contain only a natural fiber asits constituent fiber. A feature of the fiber sheet 11 having such asingle-component fiber form is that the fiber sheet 11 exhibitsexcellent repeated water absorbency and is less irritating to the skin.As the fiber sheet 11 having a single-component fiber form, woven clothsor knitted cloths made of a cotton fiber are especially preferable thatare produced by spinning a cotton fiber as the natural fiber and weavingor knitting the cotton fiber in any of various manners.

One of main features of the water repellency-imparted underpants 10 asan embodiment of the water repellency-imparted fiber article of thepresent invention is as follows. As shown in FIGS. 1 and 2, the waterrepellency-imparted underpants 10 have a non-skin-side water-repellentregion 2 on the outer surface (i.e., the non-skin-facing surface 1 b) ofthe underpants 1 (fiber article), the non-skin-side water-repellentregion 2 including a portion to which the water repellency-impartingagent is attached; and the water repellency-imparted underpants 10 alsohave a water absorbing layer in a section of the underpants 1 thatoverlaps the non-skin-side water-repellent region 2 in a plan view andon the side that is closer to the skin of a wearer (indicated by thereference numeral 100 in the drawings) than the non-skin-sidewater-repellent region 2, the water absorbing layer maintaining theabove-described water absorbency, that is, the “water absorbency interms of a water absorption time of 30 seconds or less as measured inaccordance with the dropping method of JIS-L-1907”. It is the fibersheet 11 that functions as the water absorbing layer in the waterrepellency-imparted underpants 10. In short, in the waterrepellency-imparted underpants 10, the fiber sheet 11, which serves asthe water absorbing layer, and the non-skin-side water-repellent region2 are provided in that order from the side closer to the skin of thewearer of the underpants in the thickness direction thereof.

In the water repellency-imparted underpants 10, the non-skin-sidewater-repellent region 2 functions as a bodily fluid barrier layer forpreventing a liquid from seeping out of the fiber sheet 11, which is thewater absorbing layer. For example, in a state in which the trousers 20as the outer clothing are worn on the water repellency-impartedunderpants 10 as the inner clothing as shown in FIG. 2, if urine isexcreted in an amount as small as about 1 mL or less from an excretionpart (penis) of the wearer 100 of the underpants (in other words,so-called “after-dribble” occurs), there is concern that the excretedurine will pass through the fiber sheet 11 as the water absorbing layerin the thickness direction thereof and reach the trousers 20, problemsarising such as making a urine stain (wet stain) that is externallyvisible on the trousers 20 and diffusing the odor of urine into thesurroundings. However, in the water repellency-imparted underpants 10,the non-skin-side water-repellent region 2 functions as the bodily fluidbarrier layer, or more specifically, a stain barrier layer, therebypreventing the urine from transferring toward the trousers 20, andtherefore, the above-described problems can be prevented.

Moreover, even though the water repellency-imparted underpants 10 adoptthe measure to prevent bodily fluid seepage, specifically, the formationof the non-skin-side water-repellent region 2, the basic configurationof the water repellency-imparted underpants 10 is substantiallyunchanged from the configuration of the underpants 1 (fiber article),which is the base thereof. Therefore, while the measure to preventbodily fluid seepage is adopted, this is unlikely to be noticed by otherpeople, and it is possible to use the water repellency-impartedunderpants 10 with the same feeling as when wearing common underwear.Moreover, the non-skin-side water-repellent region 2 is formed on onlythe non-skin-facing surface 1 b of the underpants 1, and the influencesof the formation of the non-skin-side water-repellent region 2 on theunderpants 1 are minimized. Therefore, the basic performance, such asthe appearance, wearing comfort, and water absorbency, of the waterrepellency-imparted underpants 10 is by no means inferior to, and insome cases may even be superior to, the intrinsic performance of theunderpants 1, and the water repellency-imparted underpants 10 also haveexcellent texture, usage feel, and the like.

In the water repellency-imparted underpants 10, the non-skin-sidewater-repellent region 2 is formed partially on the non-skin-facingsurface 1 b (non-skin-facing surface of the fiber sheet 11) of theunderpants 1. Specifically, as shown in FIGS. 1 and 2, the non-skin-sidewater-repellent region 2 is formed in only a section of the front bodyportion of the underpants 1 that faces the excretion part (penis) of thewearer 100 of the underpants, and has a substantially quadrangular shapein a plan view.

In the water repellency-imparted fiber article of the present invention,the non-skin-side water-repellent region serving as a stain barriermaterial against bodily fluids and the like is formed on at least thenon-skin-facing surface of the fiber article, but it is not particularlylimited in what area the non-skin-side water-repellent region is formed.In short, there is no particularly limitation on in what area thenon-skin-side water-repellent region is formed as long as thenon-skin-side water-repellent region is formed so as to include asection where prevention of liquid seepage is desired. For example, inthe water repellency-imparted underpants 10, the non-skin-sidewater-repellent region 2 may be formed over the entire area of thenon-skin-facing surface 1 b in the front body portion of the underpants1. The section where the non-skin-side water-repellent region 2 isformed on the non-skin-facing surface 1 b need not be a portion thatcorresponds to the pubic region of the wearer (central portion of theunderpants 1 in a front view) as shown in FIG. 1, and it can beanywhere, and for example, can correspond to a section where the weareris especially anxious about the bodily fluid seepage. Specifically, forexample, when an imaginary center line that bisects the body of thewearer in the width direction of the wearer while extending in theheight direction of the wearer is used as a reference line, thenon-skin-side water-repellent region 2 may be formed to the right or theleft of the reference line.

In the water repellency-imparted underpants 10, the surface of thenon-skin-side water-repellent region 2 has a water contact angle of 80degrees or greater, preferably 85 degrees or greater, and morepreferably 90 degrees or greater. The contact angle is an index of thedegree of hydrophobicity of the surface of the non-skin-sidewater-repellent region 2. The greater the numerical value of the contactangle, the higher the hydrophobicity (the lower the hydrophilicity), andthe smaller the numerical value of the contact angle, the lower thehydrophobicity (the higher the hydrophilicity). If the water contactangle on the surface of the non-skin-side water-repellent region 2 isless than 80 degrees, it is not possible to prevent liquid from seepingout of the water absorbing layer (fiber sheet 11), and thus problems,specifically, a bodily fluid excreted from the body seeping into theclothing and becoming externally visible, cannot be prevented fromarising.

Conventionally, in the context of imparting water repellency to anobject (fiber article), it is common that “water repellency” to beimparted is greater than 90 degrees in terms of the water contact angleas an index. However, the conditions that liquid transfer from the innerclothing side, such as a piece of underwear, to the outer clothing side,such as a pair of trousers, can be prevented, and that liquid can beconfined to the inside of the inner clothing suffice for the technicalidea of the present invention. For this purpose, the condition that asufficiently lower degree of hydrophilicity (higher degree ofhydrophobicity) than the hydrophilicity of the outer clothing isimparted to the inner clothing suffices. These findings have beenobtained after various studies conducted by the inventors of the presentinvention, and the above-described preferable range (80 degrees orgreater) of the water contact angle on the surface of the non-skin-sidewater-repellent region 2 is based on these findings. The contact angleis measured in accordance with the following method.

Method for Measuring Contact Angle (Contact Angle on Sheet Surface)

A measurement sample is cut from a fiber article to be measured, themeasurement sample having a quadrangular shape in a plan view with asize of 150 mm in the longitudinal direction (MD direction) and 70 mm inthe lateral direction (CD direction). The measurement sample is allowedto stand for twenty-four hours in a predetermined measurementenvironment for conditioning. With regard to the measurementenvironment, the temperature is set at 23±2° C., and the relativehumidity is set at 50±5% RH. A drop of ion exchanged water is attachedto a surface (non-skin-side water-repellent region) of the measurementsample on which the contact angle is to be measured. The image of thedrop is recorded, and the contact angle is measured on the recordedimage. More specifically, a microscope VHX-1000 manufactured by KeyenceCorporation is used as the measuring apparatus, and amedium-magnification zoom lens is attached to the microscope in a statein which the zoom lens is tilted to 90°. The measurement sample isplaced on a measurement stage of the measuring apparatus such that thesurface to be measured faces upward and can be observed in the CDdirection of the measurement sample. Then, a drop of 3 μL of ionexchanged water is attached to the surface to be measured, of themeasurement sample placed on the measurement stage, and images of thatdrop are recorded and captured into the measuring apparatus. At thistime, the images are captured in 3 seconds. Out of the plurality ofrecorded images, ten images in which both ends or one end of the drop inthe CD direction is clear are selected, and for each of the ten images,the contact angle of the drop is measured based on a reference plane.The average value of the found contact angle values is taken as thecontact angle on that measured surface (surface of the non-skin-sidewater-repellent region) of the fiber article of interest.

In the above-described method for measuring the contact angle, thesurface unevenness may be significant depending on the weave structureof the fabric of the fiber article to be measured, and this may make itimpossible to define the reference plane in magnified observation. Inthat case, the measurement can be performed in the same manner as in themethod described above, except that the amount of drop of ion exchangedwater attached is changed from 3 μL to 0.1 mL, the drop being attachedin a stationary manner using a Komagome pipette, and that images arecaptured unmagnified (1/1).

Moreover, instead of the above-described “water contact angle”, the“water repellency angle”, which is measured using the following method,can also be used as an index of the degree of hydrophobicity of thesurface of the non-skin-side water-repellent region. The term “waterrepellency angle” as used herein, may also be referred to as the“sliding angle”. Depending on, for example, the type of the fiberarticle having the non-skin-side water-repellent region, the waterrepellency angle may be measured in a more practical condition than thewater contact angle, and can more properly indicate the degree ofhydrophobicity of the surface of the non-skin-side water-repellentregion.

Method for Measuring Water Repellency Angle (Sliding Angle)

A measurement sample is cut from a fiber article to be measured, themeasurement sample having a quadrangular shape in a plan view with asize of 150 mm in the longitudinal direction (MD direction) and 70 mm inthe lateral direction (CD direction). The measurement sample is allowedto stand for twenty-four hours in a predetermined measurementenvironment for conditioning. With regard to the measurementenvironment, the temperature is set at 23±2° C. and the relativehumidity is set at 50±5% RH. The measurement sample is fixed to one sideof a 1-mm thick acrylic plate that has smooth surfaces. When fixing themeasurement sample to the acrylic plate, it is preferable to extend thefour sides of the measurement sample and fix the four sides withpressure-sensitive adhesive tape or the like so as not to form wrinkleson the measurement sample.

The acrylic plate to which the measurement sample is fixed is inclinedrelative to a horizontal plane, with the surface to which themeasurement sample is fixed facing upward, and is fixed in this state. Adrop of 0.1 mL of ion exchanged water is gently dropped onto themeasurement sample from a position that is 10 mm above the measurementsample. The dropping operation in this manner is performed a pluralityof times while the angle between the acrylic plate and the horizontalplane, that is, “the inclination angle of the measurement sample” ischanged as appropriate. The inclination angle of the measurement samplewhen the drop is not absorbed by the measurement sample at the droppedposition and rolls down the inclined surface of the measurement samplefor a distance of 30 mm or greater is taken as the water repellencyangle (sliding angle) of the measured surface (surface of thenon-skin-side water-repellent region) of the fiber article of interest.

Usually, the water repellency angle (sliding angle) is within a range ofgreater than 0 degrees and less than 90 degrees, and as the value of thewater repellency angle is smaller, it can be determined that themeasured surface (surface of the non-skin-side water-repellent region)is more water-repellent, and therefore that the measured surface easilyrepels the drop. Thus, when the surface of the non-skin-sidewater-repellent region in the present invention is a water-repellentsurface having a relatively low water repellency angle, seepage of aliquid to the outer clothing side, such as a pair of trousers, can beeffectively prevented. From this point of view, in the waterrepellency-imparted underpants 10, a water repellency angle of thesurface of the non-skin-side water-repellent region 2 on thenon-skin-facing surface 1 b is 45 degrees or less, preferably 40 degreesor less, and more preferably 30 degrees or less.

With regard to the skin-facing surface 1 a of the underpants 1, thefiber sheet 11, which serves as the water absorbing layer maintainingthe above-described water absorbency (water absorbency in terms of awater absorption time of 30 seconds or less as measured in accordancewith the dropping method of JIS L-1907), needs to be provided in asection that overlaps the non-skin-side water-repellent region 2 in aplan view and on a side that is closer to the skin of the user than thenon-skin-side water-repellent region 2 as described above, and acomfortable usage feel without a wet feel is required in contrast to thenon-skin-facing surface 1 b. Taking these requirements into account, itis not preferable that the skin-facing surface 1 a of the underpants 1be excessively water-repellent. From this point of view, the skin-facingsurface 1 a has a water contact angle of preferably 60 degrees or less,and more preferably 40 degrees or less. The skin-facing surface 1 a iseven more preferably configured such that, when a drop of ion exchangedwater is attached to the skin-facing surface 1 a as a surface to bemeasured in the above-described measurement method, the drop is absorbedinto the underpants 1 via the skin-facing surface 1 a almostsimultaneously (instantly) with the attachment of the drop thereto. Inother words, the skin-facing surface 1 a of the underpants 1 even morepreferably has high water absorbency such that the measurement of thecontact angle of ion exchanged water is impossible. From the same pointof view, the skin-facing surface 1 a has a water repellency angle(sliding angle) of preferably 50 degrees or greater, and more preferably55 degrees or greater. The skin-facing surface 1 a is even morepreferably configured such that, irrespective of the water repellencyangle, a drop dropped onto the measurement sample in the above-describedmeasurement method is quickly absorbed at the dropped position withoutrolling down the inclined surface.

In the fiber article, if a portion of the skin-facing surface thereofthat is located on the opposite side to the non-skin-sidewater-repellent region (portion where the water repellency-impartingagent is attached) has a water contact angle of greater than 60 degreesor a water repellency angle of less than 50 degrees, or has high waterabsorbency such that the measurement of contact angle is impossible asdescribed above, it can be determined that this fiber article does nothave a water absorbing layer which maintains the above-described waterabsorbency and is located in a section that overlaps the non-skin-sidewater-repellent region in a plan view and on a side that is closer tothe skin of the user than the non-skin-side water-repellent region.

As described above, the water contact angle or the water repellencyangle (sliding angle) may be used as the index of the degree ofhydrophobicity of the surface of the non-skin-side water-repellentregion, or further, the skin-facing surface or the non-skin-facingsurface of the fiber article. For the water repellency-impartedunderpants 10, it is preferable that the surface of the non-skin-sidewater-repellent region 2 have a water contact angle within theabove-described preferable range and also has a water repellency anglewithin the above-described preferable range.

Moreover, in addition to a water contact angle of 80 degrees or greateror a water repellency angle of 45 degrees or less, the surface of thenon-skin-side water-repellent region 2 provides a water absorption rateof 10 seconds or greater, preferably 25 seconds or greater, and morepreferably 40 seconds or greater. The water absorption rate as usedherein is expressed as the time taken for a predetermined amount ofwater to be absorbed (i.e., water absorption time), and it is determinedthat as the numerical value of the water absorption rate is greater (thewater absorption time is longer), the water absorption rate is slower.When the surface of the non-skin-side water-repellent region 2 has awater absorption rate of 10 seconds or greater, the amount of waterabsorbed on the non-skin-facing surface 1 b side, on which thenon-skin-side water-repellent region 2 has been provided, of theunderpants 1 is relatively small, compared with that on the skin-facingsurface 1 a side, which is located on the opposite side to thenon-skin-facing surface 1 b side. Therefore, a liquid that is absorbedon the skin-facing surface 1 a side is effectively suppressed fromtransferring to the non-skin-facing surface 1 b side, and consequentlyseepage of the liquid into the trousers 20 can be even more effectivelyprevented. If the water absorption rate of the surface of thenon-skin-side water-repellent region 2 is less than 10 seconds, seepageof a liquid out of the water absorbing layer (fiber sheet 11) cannot beprevented, and therefore, it is not possible to prevent problems,specifically, a bodily fluid excreted from the body seeping into theclothing and becoming externally visible. The water absorption rate ismeasured in accordance with the method described later.

Moreover, in view of even further increasing the effect of preventing aliquid from seeping into the trousers 20, it is preferable that thewater absorption rate (water absorption time) of the surface of thenon-skin-side water-repellent region 2 is slower, by 5 seconds orlonger, than that of the surface of a portion of the skin-facing surface1 a of the underpants 1 that is located on the opposite side to thenon-skin-side water-repellent region 2. Moreover, in view of achievingboth the effective prevention of liquid seepage into the trousers 20 andthe air permeability, the water absorption rate is preferably 600seconds or less, and more preferably 300 seconds or less.

Method for Measuring Water Absorption Rate

Five measurement samples are cut from a fiber article to be measured,the measurement samples each having a quadrangular shape in a plan viewwith a size of 200 mm in the longitudinal direction (MD direction) and200 mm in the lateral direction (CD direction). The measurement samplesare allowed to stand for twenty-four hours in a predeterminedmeasurement environment for conditioning. With regard to the measurementenvironment, the temperature is set at 23±2° C., and the relativehumidity is set at 50±5% RH. The measurement of water absorption rate isperformed on these measurement samples in accordance with the methodspecified in JIS L1907, provided that the height from a surface to bemeasured of a measurement sample to the tip of a burette is changed to 5mm. The surface to be measured refers to a surface of that measurementsample on which the water absorption rate is to be measured, and iseither a skin-facing surface or a non-skin-facing surface (surface ofthe non-skin-side water-repellent region).

The water contact angle and the water absorption rate of the surface ofthe non-skin-side water-repellent region 2 can be adjusted byappropriately adjusting the type, the amount attached, the attachmentarea, and the like of the water repellency-imparting agent that formsthe non-skin-side water-repellent region 2. Moreover, as will bedescribed later, the non-skin-side water-repellent region 2 is formed byapplying the water repellency-imparting agent to the non-skin-facingsurface 1 b of the underpants 1 (fiber article) that is the base of thewater repellency-imparted underpants 10, and the water contact angle andthe water absorption rate of the surface of the non-skin-sidewater-repellent region 2 can also be adjusted by devising applicationconditions including the viscosity of the water repellency-impartingagent and the pressure applied during application.

The amount (areal weight) of the water repellency-imparting agent thatis attached to the non-skin-side water-repellent region 2 is preferably0.02 g/m² or greater, and more preferably 0.05 g/m² or greater, and ispreferably 1.5 g/m² or less, and more preferably 1.2 g/m² or less.

The non-skin-side water-repellent region 2 is a region including the“portion where the water repellency-imparting agent is attached” on thenon-skin-facing surface 1 b of the underpants 1. The non-skin-sidewater-repellent region 2 may have the following configuration i) or ii):i) the water repellency-imparting agent is applied continuously in adirection in which the plane of the non-skin-facing surface 1 b extends,and no portions to which the water repellency-imparting agent is notattached are present; or ii) both a portion to which the waterrepellency-imparting agent is attached and a portion to which the waterrepellency-imparting agent is not attached are present. In theconfiguration ii), the water repellency-imparting agent isdiscontinuously present on the non-skin-facing surface 1 b, that is, aplurality of portions to which the water repellency-imparting agent isattached are intermittently present; however the plurality of portionsto which the water repellency-imparting agent is attached are gatheredto at least an extent such that those portions can be regarded as asingle integrated region, that is, the non-skin-side water-repellentregion 2, by an observer. FIG. 4(a) is a microscope photograph (at amagnification of 50) of a specific example of a non-skin-sidewater-repellent region that has the configuration ii). In thenon-skin-side water-repellent region shown in FIG. 4(a), it can be seenthat both the portions to which the water repellency-imparting agent isattached (non-white portions) and the portions to which the waterrepellency-imparting agent is not attached (portions where the surfaceof the fiber article is exposed; white portions) are present.

As a result of applying the water repellency-imparting agent to thenon-skin-facing surface 1 b of the underpants 1 to thereby form thenon-skin-side water-repellent region 2 thereon, a bodily fluid excretedfrom the body is prevented from seeping into clothing and becomingexternally visible, but on the other hand there is concern that the airpermeability and the flexibility of a section where the non-skin-sidewater-repellent region 2 is formed will be reduced. In this context, ifboth the portions to which the water repellency-imparting agent isattached and the portions to which the water repellency-imparting agentis not attached intermingle in the non-skin-side water-repellent region2 as is in case of the above-described configuration ii) (see FIG.4(a)), reductions in air permeability and flexibility caused by theapplication of the water repellency-imparting agent are suppressed, andtherefore, the air permeability and the flexibility intrinsic to theunderpants 1 can be substantially maintained. To form a non-skin-sidewater-repellent region 2 in which both a portion to which the waterrepellency-imparting agent is attached and a portion to which the waterrepellency-imparting agent is not attached intermingle, the waterrepellency-imparting agent can be intermittently attached to thenon-skin-facing surface 1 b of the underpants 1, for example, during theproduction of the water repellency-imparted underpants 10. In order toapply the water repellency-imparting agent intermittently, a waterrepellency-imparting agent may be sprayed onto the non-skin-facingsurface 1 b with a contactless application means to apply therepellency-imparting agent such as a spray; a water repellency-impartingagent may be applied according to a roll-on method, which will bedescribed later; or a water repellency-imparting agent that issolidified into a stick-like shape may be brought into direct contactwith the non-skin-facing surface 1 b to thereby apply the waterrepellency-imparting agent thereto. A mixed state as shown in FIG. 4(a),in which both a portion to which the water repellency-imparting agent isattached and a portion to which the water repellency-imparting agent isnot attached intermingle, can be obtained by any of these methods.

FIG. 4(b) is a microscope photograph (at a magnification of 50) of theopposite side to the side on which the non-skin-side water-repellentregion is formed (side to which the water repellency-imparting agent isapplied) shown in FIG. 4(a); that is, the microscope photograph showsthe skin-facing surface (the side to which the waterrepellency-imparting agent is not applied) of the specific example ofthe water repellency-imparted fiber article of the present invention. InFIG. 4(a), the presence of the water repellency-imparting agent(non-white portions in the photograph) can be confirmed. However, inFIG. 4(b), the presence of the water repellency-imparting agent cannotbe confirmed, and merely the original surface (skin-facing surface) ofthe fiber article is extending. The fact that the presence of the waterrepellency-imparting agent cannot be confirmed in FIG. 4(b) means thatin the case where the non-skin-side water-repellent region 2 is formedby applying the water repellency-imparting agent to the non-skin-facingsurface 1 b of the underpants 1 by, for example, the roll-on methoddescribed later, it is unlikely that the applied waterrepellency-imparting agent penetrates the underpants 1 in the thicknessdirection thereof and appears on the skin-facing surface 1 a. Thus, itcan be said that there is a possibility that a “state in which theamount of water repellency-imparting agent attached decreases from thenon-skin-facing surface of the fiber article toward the skin-facingsurface thereof” will be provided by applying the waterrepellency-imparting agent to the non-skin-facing surface of the fiberarticle. This state will be described later.

In a 50-mm-square region (unit region) arbitrarily selected from thenon-skin-side water-repellent region 2, the percentage of the total areaof the portions to which the water repellency-imparting agent isattached (the occupancy ratio of portions to which the water repellencyimparting agent is attached) to the whole area of the 50-mm-squareregion is preferably 10% or greater, and more preferably 15% or greater,and is preferably 80% or less, and more preferably 60% or less. Thenon-skin-side water-repellent region 2 in which the occupancy ratio ofportions to which the water repellency imparting agent is attached iswithin the above-described range has the above-described configurationii). In the above-described configuration i), the occupancy ratio ofportions to which the water repellency imparting agent is attached is100%. If the occupancy ratio of portions to which the water repellencyimparting agent is attached is excessively low, the aforementionedfunction of the non-skin-side water-repellent region 2 as the barrierlayer is insufficient, and thus, there is a risk that the problems, suchas a bodily fluid excreted from the body seeping into clothing andbecoming externally visible, cannot be prevented. If the occupancy ratioof portions to which the water repellency imparting agent is attached isexcessively high, the applied water repellency-imparting agent maypenetrate even to the skin-facing surface 1 a on the opposite side,depending on the type or the like of the underpants 1, when the waterrepellency-imparting agent is applied to the non-skin-facing surface 1 bthereof so as to form the non-skin-side water-repellent region 2, andthis may result in a decrease in the effect of preventing liquid seepageinto the trousers 20. Moreover, if the occupancy ratio of portions towhich the water repellency imparting agent is attached is high, thefunction of the non-skin-side water-repellent region 2 as the barrierlayer is high, but on the other hand, there is a risk that the airpermeability and the flexibility of the section where the non-skin-sidewater-repellent region 2 is formed will be insufficient.

In the water repellency-imparted underpants 10, the waterrepellency-imparting agent is not attached to the skin-facing surface 1a, which is located on the opposite side to the side on which thenon-skin-side water-repellent region 2 is formed, or the waterrepellency-imparting agent is attached in an extremely small amount evenif the agent is attached to the skin-facing surface 1 a. Therefore, inthe skin-facing surface 1 a, the occupancy ratio of portions to whichthe water repellency imparting agent is attached is significantly lowerthan that of the non-skin-side water-repellent region 2. Specifically,in a 50-mm-square region (unit region) arbitrarily selected from theskin-facing surface 1 a, the percentage of the total area of theportions to which the water repellency-imparting agent is attached(occupancy ratio of portions to which the water repellency impartingagent is attached) to the whole area of the 50-mm-square region ispreferably 15% or less, more preferably 5% or less, and even morepreferably zero.

To check whether or not a portion to which a water repellency-impartingagent is attached (a non-skin-side water-repellent region according tothe present invention) is present in a fiber article, either one of thefollowing checking methods A and B can be used. No matter which of thefollowing checking methods A and B is used, the occupancy ratio ofportions to which the water repellency imparting agent is attached canbe calculated. However, in the case of the checking method B, in which ascanning electron microscope is used, the above-described unit region isset to be 2 mm square instead of 50 mm square, and in that case, theoccupancy ratio of portions to which the water repellency impartingagent is attached is preferably 10% or greater, and more preferably 15%or greater, and is preferably 80% or less, and more preferably 60% orless.

Checking Method A: A colored liquid is dropped onto a surface(non-skin-facing surface) of a fiber article to be checked. The coloredliquid is prepared by dissolving or dispersing an appropriate coloringagent (dye, pigment, or the like) in water. If no waterrepellency-imparting agent is attached to the position of the coloredliquid dropped, the portion of the fiber article corresponding to theposition of the colored liquid dropped is stained with that drop of thecolored liquid. However, if a water repellency-imparting agent isattached to the position of the colored liquid dropped, the portion ofthe fiber article corresponding to the position of the colored liquiddropped is not stained and remains in the original color since the dropof the colored liquid is repelled by the water repellency-impartingagent. Usually, by performing the operation of dropping the coloredliquid in this manner a plurality of times, a non-colored region that isnot stained becomes visually observable, and the non-colored region canbe determined to be a portion to which the water repellency-impartingagent is attached (non-skin-side water-repellent region in the presentinvention). The ratio of the area of the non-colored region to the areaof a unit region (50 mm square), the former/the latter, is theabove-described occupancy ratio of portions to which the waterrepellency imparting agent is attached.

If it is difficult to obtain the above-described ratio of thenon-colored area in the checking method A to calculate the occupancyratio of portions to which the water repellency imparting agent isattached, the following procedure can be performed. Specifically, abouttwenty drops of the colored liquid are substantially equally fallen ontoa 50-mm-square unit region in a manner such that the drops do notoverlap one another. The number of drops remaining (number of residualdrops) on the unit region for 3 seconds or longer without being absorbedis counted, and the percentage of the number of residual drops to thetotal number of the fallen drops is taken as the occupancy ratio ofportions to which the water repellency imparting agent is attached.

Checking Method B: This method is particularly effective in the casewhere the water repellency-imparting agent attached to an object to bechecked is a modified silicone-containing water repellency-impartingagent. A surface of a fiber article to be checked (non-skin-facingsurface) is observed with a scanning electron microscope (SEM) and anenergy dispersive X-ray spectrometer (EDS) attached thereto, and anobservation image is output if necessary, to check the presence orabsence of the element Si contained in the modified silicone-containingwater repellency-imparting agent. If the element Si is found, theportion where the element Si is found can be determined to be a portionto which the water repellency-imparting agent is attached (non-skin-sidewater-repellent region in the present invention). The magnificationunder an SEM is usually 50 to 100. For example, the portion to which thewater repellency-imparting agent is attached shown in the image iscopied to a transparent film, and the area percentage thereof iscomputed through image analysis, thereby obtaining the occupancy ratioof portions to which the water repellency imparting agent is attached. Aspecific example of the conditions for observation in the checkingmethod B is as follows: A JSM-6510 from JEOL (manufactured by JEOL Ltd.)is used as the SEM, an EX-230BU (built-in) is used as the EDS, themagnification is 50, and the acceleration voltage is 10 kV.

In both of the checking methods A and B, there may be steps due tounevenness of the surface (non-skin-facing surface) of the fiber articleto be checked, depending on the weave structure of the fabric of thefiber article, and in that case, the occupancy ratio of portions towhich the water repellency imparting agent is attached is calculatedwith respect to the whole surface area of the unit region including thesteps.

In the water repellency-imparted underpants 10, if the thickness 2T (seeFIG. 2) of a portion to which the water repellency-imparting agent isattached, of the non-skin-side water-repellent region 2 is excessivelysmall, there is a risk that the function of the non-skin-sidewater-repellent region 2 as the barrier layer will be insufficient. Onthe other hand, if the thickness 2T is excessively large, there is arisk that the air permeability and the flexibility will be pronouncedlyreduced compared with the state before the water repellency-impartingagent is attached, that is, the underpants 1 (fiber article). Takingthese into account, the thickness 2T of a portion to which the waterrepellency-imparting agent is attached, of the non-skin-sidewater-repellent region 2 is preferably 5% or greater, more preferably10% or greater, and even more preferably 50% or greater, and, ispreferably 60% or less, based on the thickness 1T (see FIG. 2) of theunderpants 1 (fiber article). The ratio of the thickness 2T to thethickness 1T may hereinafter also be referred to as “thickness ratio ofthe water repellency-imparting agent”. A particularly preferable rangeof the thickness ratio of the water repellency-imparting agent is from50% to 60% as described above. Preferably, the underpants 1 arerelatively thin while the thickness 2T is small, in view of maintainingas much as possible the properties of underwear intrinsic to theunderpants 1, and effectively utilizing the water absorbency intrinsicto the underpants 1.

The thickness 2T of a portion to which the water repellency-impartingagent is attached, of the non-skin-side water-repellent region 2 ispreferably 0.05 mm or greater and more preferably 0.1 mm or greater, andis preferably 0.5 mm or less.

The thickness 1T of the underpants 1 (fiber sheet 11) is preferably 0.5mm or greater, and more preferably 0.8 mm or greater, and is preferably2 mm or less, and more preferably 1.7 mm or less.

The thickness 2T can be measured using a known thickness measurementmethod, and the measurement may be facilitated by coloring the attachedwater repellency-imparting agent itself with an appropriate coloringagent prior to the measurement. When the attached waterrepellency-imparting agent is a modified silicone-containing waterrepellency-imparting agent, a measurement method that uses SEM-EDS as inthe above-described checking method B is convenient. In that case, thethickness 2T is measured in the cross-sectional direction of themeasurement sample. The observation may be performed under theconditions, for example, of a magnification of 100 and an accelerationvoltage of 10 kV. When a measurement sample is prepared by cutting apiece having a predetermined shape from the water repellency-impartedunderpants 10, a cutting method that is known to a person skilled in theart, such as use of a microtome, can be performed in order to preventcontamination of the cut surface to be observed due to the cuttingoperation, or alternatively, cutting may be performed with a FEATHERsingle edge blade razor (FAS-10) after freezing the waterrepellency-imparted underpants 10 with liquid nitrogen.

The above-described “ratio of the thickness 2T of a portion to which thewater repellency-imparting agent is attached, of the non-skin-sidewater-repellent region to the thickness 1T of the fiber article”(thickness ratio of the water repellency-imparting agent) is measured inthe following manner with the above-described SEM-EDS. Specifically, anobject to be measured (fiber article to which a waterrepellency-imparting agent is attached) is frozen with liquid nitrogen,and then a portion of the object to be measured where a portion to whichthe water repellency-imparting agent is attached (non-skin-sidewater-repellent region) is present is cut in the thickness directionthereof with a FEATHER single edge blade razor (FAS-10). The cut surfaceis observed with SEM-EDS as in the checking method B, and the thickness2T is measured. The thickness ratio of the water repellency-impartingagent is calculated from the found value and the thickness 1T.Preferably, the measurement of the thickness 2T is performed five timesat different observation positions for each single sample, and anaverage value of the five found values of the thickness 2T is used tocalculate the thickness ratio of the water repellency-imparting agent.The observation of the cut surface (measurement of the thickness 2T) canbe performed, for example, with a JSM-6510 from JEOL (manufactured byJEOL Ltd.) as the SEM and an EX-230BU (built-in) as the EDS, at amagnification of 100 and an acceleration voltage of 10 kV.

In the water repellency-imparted underpants 10, the air permeance of asection where the non-skin-side water-repellent region 2 is formed ispreferably 2 seconds/100 ml or greater, and more preferably 3seconds/100 ml or greater, and is preferably 30 seconds/100 ml or less,and more preferably 20 seconds/100 ml or less. As used herein, the“section where the non-skin-side water-repellent region is formed”refers to a section including the non-skin-side water-repellent region 2and a section of the water repellency-imparted underpants 10 (fibersheet 11) that overlaps the non-skin-side water-repellent region 2 in aplan view, or in other words, refers to a section of the waterrepellency-imparted underpants 10 other than a section where thenon-skin-side water-repellent region 2 is not formed.

If the air permeance of the section where the non-skin-sidewater-repellent region 2 is formed is excessively low, it can bedetermined that the occupancy ratio of portions to which the waterrepellency imparting agent is attached of the non-skin-sidewater-repellent region 2 is excessively high. This means that the airpermeability and the flexibility are pronouncedly reduced, compared withthose in a state before the attachment of the water repellency-impartingagent, that is, those of the underpants 1 (fiber article), andtherefore, there is a risk that problems, such as dampness and rashes,with the skin of the wearer of the underpants will occur. If the airpermeance of the section where the non-skin-side water-repellent region2 is formed is excessively high (if there is substantially no differencebetween the air permeance of the section where the non-skin-sidewater-repellent region 2 is formed and the air permeance intrinsic tothe underpants 1), it can be determined that the occupancy ratio ofportions to which the water repellency imparting agent is attached ofthe non-skin-side water-repellent region 2 is excessively low. Thismeans that the amount of water repellency-imparting agent attached isinsufficient, and therefore, there is a risk that the function of thenon-skin-side water-repellent region 2 as the barrier layer will beinsufficient.

The air permeance is measured in accordance with JIS P8117 (1998), andis defined as the time required for 100 ml of air to pass through anarea of 6.42 cm² under a certain pressure. Accordingly, high airpermeance means that much time is required for air to pass through, thatis, low air permeability. Conversely, low air permeance means high airpermeability. In this manner, the magnitude of the air permeance and thelevel of the air permeability show an inverse relationship. The airpermeance can be determined using an Oken air permeance tester.

Generally, if a fiber article is subjected to water-repellent treatmentsuch as film coating, the air permeability intrinsic to the fiberarticle significantly decreases, inducing skin problems such as dampnessand rashes. Taking this problem into account, it is preferable that thedifference between the air permeance of a section where thenon-skin-side water-repellent region 2 is formed and the air permeanceof a section where the non-skin-side water-repellent region 2 is notformed (section in which the air permeance intrinsic to the underpants 1is substantially maintained), i.e., the former—the latter, is 5seconds/100 ml or less, provided that the former >the latter.

In the water repellency-imparted underpants 10, the bending resistanceof the section where the non-skin-side water-repellent region 2 isformed is preferably 60 mm or less, and more preferably 55 mm or less,and is preferably 10 mm or greater, and more preferably 15 mm orgreater. The bending resistance of the section where the non-skin-sidewater-repellent region 2 is formed may also be an index of the occupancyratio of portions to which the water repellency imparting agent isattached of the non-skin-side water-repellent region 2. Specifically,some of the water repellency-imparting agents (e.g., a modifiedsilicone-containing water repellency-imparting agent, which will bedescribed later) that are preferable as the water repellency-impartingagent for forming the non-skin-side water-repellent region 2 have theproperty of increasing the flexibility (reducing the stiffness) of asection to which the water repellency-imparting agent is attached, inaccordance with an increase in the amount attached. When thenon-skin-side water-repellent region 2 is formed of such a specificwater repellency-imparting agent, it can be determined that theoccupancy ratio of portions to which the water repellency impartingagent is attached of the non-skin-side water-repellent region 2 is high,if the bending resistance of the section where the non-skin-sidewater-repellent region 2 is formed is low, or specifically, if thebending resistance of the section where the non-skin-sidewater-repellent region 2 is formed is not substantially different fromthe bending resistance intrinsic to the underpants 1, or is lower thanthe intrinsic bending resistance. On the other hand, if the bendingresistance of the section where the non-skin-side water-repellent region2 is formed is significantly lower than the bending resistance intrinsicto the underpants 1, that is, if the section where the non-skin-sidewater-repellent region 2 is formed is excessively softened to an extentsuch that the stiffness (resilience) is significantly reduced, it can bedetermined that the occupancy ratio of portions to which the waterrepellency imparting agent is attached of the non-skin-sidewater-repellent region 2 is excessively high. In contrast to a modifiedsilicone-containing water repellency-imparting agent, which will bedescribed later, a common water-repellent coating agent has the propertyof reducing the flexibility of a section to which the coating agent isattached in proportion to the amount of coating agent attached. Thereason for this is that a resin film is formed on the section to whichthe coating agent is attached. The bending resistance is measured by thefollowing method.

Method for Measuring Bending Resistance

The bending resistance is measured in accordance with the method A (45°cantilever method) specified in JIS L 1096 “8.21. measurement methodsfor bending resistance”. However, for convenience of preparation(sampling) of measurement samples, only the bending resistance in thelongitudinal direction of measurement samples is measured in the presentmeasurement method. If a measurement sample has wrinkles, folds, and thelike, the measurement sample is ironed before the measurement toeliminate the wrinkles, folds, and the like and then allowed to standfor twenty-four hours in the measurement environment for conditioning.

In view of preventing the presence of an excessive amount of the waterrepellency-imparting agent in the non-skin-side water-repellent region 2to thereby provide the occupancy ratio of portions to which the waterrepellency imparting agent is attached thereof within an appropriaterange, it is preferable that the bending resistance of the section wherethe non-skin-side water-repellent region 2 is formed be 60 mm or less asdescribed above, and be also equal to or lower than the bendingresistance of a section of the water repellency-imparted underpants 10(underpants 1) where the non-skin-side water-repellent region 2 is notformed, that is, a water-repellent region non-formed portion. Morespecifically, the difference between the bending resistance of thewater-repellent region non-formed portion and the bending resistance ofthe section where the non-skin-side water-repellent region 2 is formed,i.e., the former—the latter, is preferably 0 to 25 mm, and morepreferably 0 to 20 mm, provided that the former >the latter. Forexample, an example of the water repellency-imparting agent that canestablish this relationship in magnitude “(bending resistance ofwater-repellent region non-formed portion) >(bending resistance ofsection where non-skin-side water-repellent region 2 is formed)” is acomposition containing a modified silicone (modified silicone-containingwater repellency-imparting agent), which will be described later. Whenthis composition is used as the water repellency-imparting agent forforming the non-skin-side water-repellent region 2, it is preferablethat the difference between the former and the latter (the former—thelatter) be within the above-described specific range. Examples of themodified silicone contained in the composition include polyoxazolinemodified silicones and polyether modified silicones with variousmolecular weights and branching structures, and these modified siliconescan be used singly or in a combination of two or more.

In the water repellency-imparted fiber article of the present invention,it is necessary that the section to which the water repellency-impartingagent is attached, of the fiber article serving as the base thereofinclude the non-skin-facing surface of the fiber article, which is thesection where the non-skin-side water-repellent region is formed.However, with regard to the “section of the fiber article that overlapsthe non-skin-side water-repellent region in a plan view”, orspecifically, for example, the section of the underpants 1 (fiber sheet11) that overlaps the non-skin-side water-repellent region 2 in a planview in the case of the water repellency-imparted underpants 10 shown inFIG. 2, the water repellency-imparting agent may or may not be attachedto that section, provided that the water absorbing layer in which theabove-described water absorbency, that is, the “water absorbency interms of a water absorption time of 30 seconds or less as measured inaccordance with the dropping method of JIS L-1907” is maintained ispresent in that section. Even when the fiber article has a section towhich the water repellency-imparting agent is attached, theabove-described water absorbency may be maintained in that sectiondepending on the amount of water repellency-imparting agent attached,the attaching pattern of the water repellency-imparting agent, and thelike.

With respect to the attachment of the water repellency-imparting agent,the amount of water repellency-imparting agent attached may decreasefrom the non-skin-facing surface 1 b of the underpants 1 (fiber article)toward the skin-facing surface 1 a thereof, in the waterrepellency-imparted underpants 10 (water repellency-imparted fiberarticle) shown in FIG. 2 as an embodiment of the waterrepellency-imparted fiber article of the present invention. In this casewhere the amount of water repellency-imparting agent attached decreases,no water repellency-imparting agent may be attached to the skin-facingsurface 1 a side (region spanning from the skin-facing surface 1 a for apredetermined length in the thickness direction of the underpants 1). Aswill be described later, the non-skin-side water-repellent region 2 istypically formed by applying the water repellency-imparting agent to thenon-skin-facing surface 1 b of the underpants 1 with a spray or thelike. When the water repellency-imparting agent is applied from thenon-skin-facing surface 1 b side of the underpants 1 in this manner, theapplied water repellency-imparting agent is attached to only thenon-skin-facing surface 1 b to form the non-skin-side water-repellentregion 2 thereon, or the applied water repellency-imparting agent formsthe non-skin-side water-repellent region 2 and further penetrates intothe underpants 1 (fiber sheet 11). In both cases, the above-described“state in which the amount of water repellency-imparting agent attacheddecreases from the non-skin-facing surface of the fiber article towardthe skin-facing surface thereof” is consequently obtained. As describedabove, FIG. 4(a) shows a non-skin-facing surface of a specific exampleof this state, and FIG. 4(b) shows a skin-facing surface on the oppositeside to the non-skin-facing surface.

FIG. 5 shows an EDS image (at a magnification of 100) of a cross sectiontaken along the thickness direction of a specific example of theabove-described “state in which the amount of water repellency-impartingagent attached decreases from the non-skin-facing surface of the fiberarticle toward the skin-facing surface”. In FIG. 5, a white portionextending in the lateral direction of the image at the middle of theimage in the vertical direction thereof is the fiber article(constituent fibers), and minute dots (black spots) that are present inthe substantially upper half of the white portion are the waterrepellency-imparting agent, or more specifically, the element Sicontained in a modified silicone-containing water repellency-impartingagent, which is a type of water repellency-imparting agent. In thespecific example of the water repellency-imparted fiber article of thepresent invention shown in FIG. 5, the above-described dots are presentsuch that a relatively large number of dots are located on thenon-skin-facing surface side (upper surface side of the sheet in FIG.5), and that a relatively small number of dots are located on theskin-facing surface side (lower surface side of the sheet in FIG. 5).When the amount of water repellency-imparting agent attached decreasesfrom the non-skin-facing surface 1 b toward the skin-facing surface 1 ain this manner, it is unlikely that the skin-facing surface 1 a side(skin-facing surface 1 a and the vicinity thereof) of the waterrepellency-imparted underpants 10 is affected by the waterrepellency-imparting agent, and therefore, the tactile feel intrinsic tothe underpants 1 is retained, which is even more preferable.

Moreover, with respect to the attachment of the waterrepellency-imparting agent, the water repellency-imparted underpants 10as shown in FIG. 2 as an embodiment of the water repellency-impartedfiber article of the present invention may have a skin-sidewater-repellent region (not shown) on the skin-facing surface 1 a of theunderpants 1 (fiber article), the skin-side water-repellent regionincluding a portion to which the water repellency-imparting agent isattached. In this case where the skin-side water-repellent region isformed, the amount of water repellency-imparting agent attached per unitarea in the skin-side water-repellent region is smaller than that in thenon-skin-side water-repellent region 2. Moreover, in this case where theskin-side water-repellent region is formed, the water absorbing layer inwhich the above-described water absorbency, that is, the “waterabsorbency in terms of a water absorption time of 30 seconds or less asmeasured in accordance with the dropping method of JIS L-1907” ismaintained is present between the non-skin-side water-repellent region 2and the skin-side water-repellent region. In the case where theskin-side water-repellent region is formed, the water repellency isimparted to the skin-facing surface of the fiber article by forming theskin-side water-repellent region thereon, and therefore, the effect ofreducing the sticky feel to the skin of the user can be obtained. Theratio of the amount of water repellency-imparting agent attached in theskin-side water-repellent region to the amount of waterrepellency-imparting agent attached in the non-skin-side water-repellentregion, the former/the latter, is preferably ⅕ or less, and morepreferably 1/10 or less, and it is also preferable that no waterrepellency-imparting agent is observed in the skin-side water-repellentregion.

FIG. 3 shows another embodiment of the water repellency-imparted fiberarticle of the present invention. For the other embodiment describedbelow, components that are different from those of the above-describedwater repellency-imparted underpants 10 will be described primarily, andthe same components are denoted by the same reference numerals as in theabove-described embodiment to omit their descriptions. Descriptions ofthe water repellency-imparted underpants 10 are appropriately applied tothose components that will not be particularly described.

In a pair of water repellency-imparted underpants 10A (waterrepellency-imparted fiber article), which are a piece of inner clothing,shown in FIG. 3, the skin-facing surface 1 a of a pair of underpants 1A(fiber article) is a flat surface with substantially no unevenness,whereas the non-skin-facing surface 1 b thereof has an uneven structureconstituted by a plurality of projections and depressions. A waterrepellency-imparting agent that forms a non-skin-side water-repellentregion 2A is attached to the projections constituting the unevenstructure. The water repellency-imparting agent is not attached to thedepressions constituting the uneven structure, or even if the waterrepellency-imparting agent is attached to the depressions, the amountattached thereto is smaller than the amount attached to the projections.The uneven structure of the non-skin-facing surface 1 b of theunderpants 1A can be formed by a known embossing process, such as anembossing process with or without heat, an ultrasonic embossing process,or the like. When the material of the fiber sheet 11 of the underpants1A is a woven fabric or a knitted fabric, the uneven structure can alsobe given by devising the weaving or knitting pattern appropriately.

The “uneven structure” herein means a structure constituted by aplurality of projections that are formed by the weave or knit textureand depressions that are formed between the plurality of projections.When 60% or greater of the plurality of depressions that are present onthe surface (non-skin-facing surface) of the fiber article have a largerarea than a square of side 500 μm in a plan view and also have a depth(length from the top of a projection adjacent to the depression to thebottom of that depression) of 500 μm or greater, it can be said that thesurface (non-skin-facing surface) of the fiber article has an unevenstructure.

For example, with respect to the non-skin-side water-repellent region 2shown in FIG. 2, the skin-facing surface 1 a of the underpants 1, onwhich the non-skin-side water-repellent region 2 is formed, is a flatsurface with substantially no unevenness, and therefore, the surface ofthe non-skin-side water-repellent region 2 also is a flat surface withsubstantially no unevenness. In this case, almost the entire area of thenon-skin-side water-repellent region 2 can come into contact with thetrousers 20, which are a piece of outer clothing. Thus, vapor that isproduced in an inner space (between the skin of the wearer of theunderpants and the skin-facing surface 1 a of the underpants 1) of theunderpants 1 when worn is unlikely to be discharged to the outside.Therefore, there is concern that the trousers 20 will get wet with thevapor, and there also is concern that skin problems such as dampness andrashes will occur. This vapor is produced by evaporation of bodilyfluids, such as urine and sweat, that are excreted by the wearer of theunderpants due to body heat. In contrast, with respect to thenon-skin-side water-repellent region 2A shown in FIG. 3, the surface ofthe non-skin-side water-repellent region 2A that faces the trousers 20has the uneven structure. Accordingly, the area thereof contact with thetrousers 20 is reduced compared with that of the non-skin-sidewater-repellent region 2, and a gap that can function as an air passagemay be formed in a portion that is in contact with the trousers 20.Therefore, the above-described concern is eradicated. In this manner,the water repellency-imparted underpants 10A, which includes thenon-skin-side water-repellent region 2A having the uneven surface, hasan excellent quick-drying, so that the sticky feel is even furtherreduced.

Hereinafter, the water repellency-imparting agent used in the presentinvention will be described.

The water repellency-imparting agent that is used in the presentinvention is required to be able to impart water repellency(waterproofness) to the fiber article and form a non-skin-sidewater-repellent region that has a water contact angle and a waterabsorption rate within the above-described specific ranges.

Moreover, as described above, in the water repellency-imparted fiberarticle of the present invention, the “water absorbing layer”maintaining the water absorbency intrinsic to the fiber article needs tobe present in a section of the fiber article that overlaps thenon-skin-side water-repellent region in a plan view and on a side thatis closer to the skin of the user than the non-skin-side water-repellentregion. When the water repellency-imparting agent is applied to one side(non-skin-facing surface) of the fiber article, it is difficult tosecure the above-described water absorbing layer if the applied waterrepellency-imparting agent highly penetrate to transfer to the otherside (skin-facing surface), and furthermore, in this case, there isconcern that the air permeability, the flexibility, and the like of thefiber article will be significantly reduced.

The water repellency-imparting agent is therefore required not only tobe able to impart water repellency to the fiber article but also to havelow penetrability in the fiber article and, when applied to the fiberarticle, stay at the applied position and the vicinity thereof(non-penetrability).

An example of the water repellency-imparting agent that is used in thepresent invention is a composition containing a modified silicone(modified silicone-containing water repellency-imparting agent). Themodified silicone is a component that functions as a water repellent andimparts water repellency to the fiber article. Examples of the modifiedsilicone include polyoxazoline modified silicones and polyether modifiedsilicones with various molecular weights and branching structures, andthese modified silicones can be used singly or in a combination of twoor more. Among these modified silicones, a polyoxazoline modifiedsilicone containing 55% to 98% of a dimethyl siloxane structure, such asa silicone unit, can achieve both the stability of water repellencyafter treatment and the ability to be washed off through a commonwashing operation, and is therefore preferably used in the presentinvention. In view of obtaining stable water repellency, the modifiedsilicone content in the water repellency-imparting agent is preferably25 mass % or greater, and more preferably 30 mass % or greater withrespect to the total mass of the water repellency-imparting agent. Whena composition containing a modified silicone is used as the waterrepellency-imparting agent, the modified silicone, which is a componentof the composition and serves as the main causative substance of waterrepellency, deposits, in preference to the other components of thecomposition, on the surface (surface of the non-skin-sidewater-repellent region) of the portion of the fiber article to which thecomposition is attached, and therefore, an advantage that thecomposition can be used (attached) in a relatively small amount can beobtained.

The composition containing a modified silicone may also contain avolatile solvent in which the modified silicone is soluble. In otherwords, the water repellency-imparting agent that is used in the presentinvention may be in a liquid form in which the modified silicone isdissolved in the volatile solvent at normal temperature and pressure.The non-skin-side water-repellent region is formed by applying the waterrepellency-imparting agent in this liquid form to the non-skin-facingsurface of the fiber article, and the water repellency-imparted fiberarticle of the present invention is thus obtained. In the thus obtainedwater repellency-imparted fiber article, the volatile solvent containedin the water repellency-imparting agent in this liquid form may havevolatilized and no longer remain. Examples of the volatile solventinclude ethanol, methanol, isopropyl alcohol, and water/ethanol mixedliquids with various mixing ratios, and these volatile solvents can beused singly or in a combination of two or more. Among these volatilesolvents, ethanol has high safety and volatility (quick-drying ability),and is therefore preferably used in the present invention.

The composition containing a modified silicone may also contain awater-soluble binder. The water-soluble binder primarily functions tofix the modified silicone, which is a water repellent, to an object(fiber article) to which the composition is applied. Binders of thistype include non-water-soluble binders that are insoluble orsemi-soluble in water, and water repellency-imparting agents incommercially-available waterproofing sprays for clothes often contain anon-water-soluble binder. However, if a water repellency-imparting agentcontaining a non-water-soluble binder is applied to a fiber article,yellowing and stiffening of the fiber article, an unpleasant solventodor, and the like tend to occur, and also there may be limitations onwashing of the fiber article. Thus, the handleability of the fiberarticle may be reduced. In contrast, when a water-soluble binder isselected, these problems caused by use of a non-water-soluble binder areunlikely to occur.

Examples of the water-soluble binder include polyvinyl alcohols, acrylicresins, and acrylic resin emulsions, and these water-soluble binders canbe used singly or in a combination of two or more. Among thesewater-soluble binders, various acrylic resins, such as (vinyl methylether/butyl maleate) copolymers typified by “Gantrez ES-425” availablefrom Matsumoto Trading Co., Ltd., and acrylic resin alkanolamines arestrongly attached to the surface of the fiber article via an ester bond,and are therefore preferably used in the present invention. Such strongattachment of various acrylic resins to the fiber article via an esterbond is especially pronounced in the case where such an acrylic resin isincorporated into a polyether modified silicone-containing waterrepellency-imparting agent and, furthermore pronounced by a heatingoperation, such as ironing or drying, in such a case. The water-solublebinder content in the water repellency-imparting agent is preferably 20mass % or greater, and more preferably 30 mass % or greater, and ispreferably 80 mass % or less, and more preferably 70 mass % or less,with respect to the total mass of the water repellency-imparting agent.

In an embodiment of the water repellency-imparted fiber article of thepresent invention, the water repellency (waterproofness) can be removedby washing the water repellency-imparted fiber article with water by ausual method. That is to say, in an embodiment of the waterrepellency-imparted fiber article of the present invention, washing ofthe water repellency-imparted fiber article can removes the waterrepellency-imparting agent to eliminate the non-skin-sidewater-repellent region, thereby turning the water repellency-impartedfiber article into the original fiber article. Such a waterrepellency-imparted fiber article whose water repellency can be removedthrough washing is especially useful in the case where thewater-repellent treatment of a fiber article with a waterrepellency-imparting agent (production of a water repellency-impartedfiber article) is performed privately or in the home, rather thanindustrially. In other words, for example, a series of operations of“washing the water repellency-imparted fiber article after use to turnthe water repellency-imparted fiber article into the original fiberarticle; then storing the fiber article; and performing thewater-repellent treatment of the fiber article with the waterrepellency-imparting agent if the need to impart water repellency to thefiber article arises thereafter” can be repeatedly performed privatelyor in the home.

The above-described “water repellency-imparted fiber article whose waterrepellency can be removed by washing” can specifically be defined asfollows. A water repellency-imparted fiber article is immersed in aliquid containing 0.1 mass % of a commonly available detergent forclothing and ion exchanged water under stirring for 10 minutes, and thenthe water repellency-imparted fiber article is lightly squeezed andfurther immersed in ion exchanged water under stirring at a rotationalspeed of 350 rpm for 10 minutes. If the amount of waterrepellency-imparting agent contained in the water repellency-impartedfiber article after such a washing procedure is 20 mass % or less basedon that before the washing procedure, the water repellency-impartedfiber article is regarded as being a water repellency-imparted fiberarticle whose water repellency can be removed by washing. A surfactantincluding mainly of a long-chain alkyl ether sulfate or the like can beused as the “commonly available detergent for clothing”, and commoncommercially available detergents for clothing can generally be used.Specifically, for example, a liquid detergent for clothing “Attack Neo”(registered trademark) manufactured by Kao Corporation can be used. Thestate where “the water repellency-imparted fiber article is lightlysqueezed” can be specifically exemplified by the following: twentysheets of filter paper “2” of a size larger than a fiber article to besqueezed are laid one on top of another, the fiber article is placed ontop of the stack of the filter paper sheets, and a pressure is appliedto the whole by passing a 5-kg roller (width: 50 mm) back and forth tothereby squeeze the fiber article.

Supplementary explanations of the conditions and the like of the washingof the water repellency-imparted fiber article will be given below.Conditions, such as the volume of a tub that is used for immersion ofthe water repellency-imparted fiber article under stirring, may be setas appropriate within the range of conditions disclosed herein.Favorable conditions for washing a single fiber article may be, forexample, as follows: a beaker having a volume of 2 L is used as the tubfor immersion of the water repellency-imparted fiber article understirring, and 1.5 L of washing liquid and 1.5 L of rinsing liquid areused. Moreover, for stirring, a stirrer whose rotational speed can bemonitored can be used as appropriate, and preferably, a magnetic stirrerHS-50D manufactured by AS ONE Corporation is used in a combination withan AS ONE Crosshead Rotor Double (diameter: 60 mm, product number:1-5409-07) as a stirrer bar.

FIG. 6 shows a specific example of the water repellency-imparted fiberarticle of the present invention after immersion under stirring (i.e.,after washing) in accordance with the above-described procedures. Beforewashing, this water repellency-imparted fiber article is the waterrepellency-imparted fiber article shown in FIG. 5, in which the amountof water repellency-imparting agent attached decreases from thenon-skin-facing surface of the fiber article toward the skin-facingsurface. FIG. 6 is an EDS image (at a magnification of 100) of a crosssection of that specific example taken along the thickness directionthereof. In the water repellency-imparted fiber article before washingin FIG. 5, the water repellency-imparting agent (element Si derived fromthe modified silicone-containing water repellency-imparting agent) canbe observed as a large number of dots (black spots) on thenon-skin-facing surface side (upper surface, and the vicinity thereof,of the white portion in FIG. 5) thereof; however, it can be seen thatthe water repellency-imparting agent have almost completely disappearedin the water repellency-imparted fiber article after washing shown inFIG. 6. For this reason, it can be understood that the specific exampleof the water repellency-imparted fiber article of the present inventionshown in FIG. 5 is the “water repellency-imparted fiber article whosewater repellency can be removed by washing”.

The percentage of the water repellency-imparting agent remaining in thewater repellency-imparted fiber article after washing can be actuallymeasured through sampling, or alternatively it can be roughly measuredby placing a drop of liquid on the water repellency-imparted fiberarticle and observing the state of the liquid absorption, forconvenience's sake. Specifically, for example, the percentage of thewater repellency-imparting agent remaining on that surface can bedetermined as zero in the following case: with respect to thewater-repellency of the non-skin-facing surface (non-skin-sidewater-repellent region) of the water repellency-imparted fiber article,the non-skin-facing surface of the water repellency-imparted fiberarticle before washing exhibits relatively strong water repellency,specifically, a water contact angle of 80 degrees or greater as measuredby the above-described method, and after washing, that non-skin-facingsurface exhibits a contact angle equal to that of the skin-facingsurface of the water repellency-imparted fiber article, or absorbs soinstantly the drop of ion exchanged water used in the measurement of thecontact angle that it is impossible to measure the contact angle.

The “water repellency-imparted fiber article whose water repellency canbe removed through washing” can be obtained by using the above-describedwater-soluble binder as the binder contained in the waterrepellency-imparting agent. The “water repellency-imparted fiber articlewhose water repellency can be removed by washing” can also be obtainedby using, as the water repellency-imparting agent, a modifiedsilicone-containing water repellency-imparting agent that contains amodified silicone having a hydrophilic polymer as a hydrophilic sidechain as a modified group. In the latter case, the whole of the waterrepellency-imparting agent may be composed of one or more of suchmodified silicone-containing water repellency-imparting agents, or thewater repellency-imparting agent may be composed mainly of one or moreof such modified silicone-containing water repellency-imparting agentsand further contain one or more other water repellency-imparting agentsin a smaller amount. In such a modified silicone-containing waterrepellency-imparting agent, the mass ratio of the hydrophilic side-chaincontent to the silicone principal-chain content is preferably from 55 to98 mass %.

The water repellency-imparted fiber article of the present invention mayalso contain, as a measure against odor (also referred to as anodor-preventing agent), if necessary, at least one selected from thegroup consisting of a deodorizing ingredient, an odor-removingingredient, a fragrant ingredient, an antimicrobial agent, abactericidal agent, and a refreshing agent. The odor-preventing agentmay be contained in the fiber article or the non-skin-sidewater-repellent region constituting the water repellency-imparted fiberarticle. For example, in a water repellency-imparted fiber articleobtained by applying a water repellency-imparting agent (compositioncontaining a modified silicone) containing an odor-preventing agent to afiber article that does not contain an odor-preventing agent, theodor-preventing agent is contained in at least the non-skin-sidewater-repellent region, and depending on the conditions for applying thewater repellency-imparting agent and other conditions, theodor-preventing agent may also be contained in the fiber article. Thesemeasures against odor are also preferable in light of the effect ofsuppressing rashes and the like of the skin. Preferably, which of theabove-described ingredients and agents is used as the measure againstodor is determined with consideration given to the influence on, forexample, the safety of the body of the user at a section for which thatingredient or agent is used.

Examples of the deodorizing ingredient and the odor-removing ingredientinclude known odor removers, such as particles having a layeredstructure and made of activated carbon, silica gel, zeolite, or azirconium phosphate; particles having a stereostructure made of asilicate; and zinc oxide, and these odor removers can be used singly orin a combination of two or more.

A natural fragrance or a synthetic fragrance may be used in anappropriate amount as the fragrant ingredient. Examples of the naturalfragrance include fragrances extracted from naturally occurringsubstances, such as green tea, benzoin, clove oil, jasmine absolute,mate, mimosa, Tonkin musk, frankincense, rosemary oil, sandalwood oil,vetiver oil, and violet leaf absolute, and examples of the syntheticfragrance include higher alcohols, aldehydes, benzaldehydes, benzoicacid, cinnamic acid, cinnamaldehydes, cinnamyl alcohols, coumarin,esters, indole, ketones, alicyclic acid and related compounds,terpenoids, and vanillin. These fragrances can be used singly or in acombination of two or more.

As the antimicrobial agent and the bactericidal agent, any of knownantimicrobial and bactericidal substances can be used. Examples thereofinclude silver, copper, zinc, silica, activated carbon, aluminosilicatecompounds, zeolite, electrolytes that can be used as moisture absorbingmaterials, and alcohols, aldehydes, phenols, hydrogen peroxides,chlorine, hypochlorites, and surfactants. These substances can be usedsingly or in a combination of two or more.

A refreshing agent disclosed in Japanese Patent No. 6121269, forexample, can be appropriately used as the refreshing agent. When arefreshing agent is contained the water repellency-imparted fiberarticle, the refreshing agent imparts a feel of refreshment and a dryfeel to the water repellency-imparted fiber article, and thus, thecomfort can be further improved.

As described above, the water repellency-imparted fiber article of thepresent invention has water absorbency, which is intrinsic to the fiberarticle, and water repellency, which is provided by the non-skin-sidewater-repellent region, and can be applied to various uses by making themost of these features. For example, the water repellency-imparted fiberarticle can be applied to inner clothing typified by underwear, such asunderpants, loincloths, shirts, brassieres, girdles, and socks; sportingclothing, such as football shirts, golf shirts, tennis shirts,basketball shirts, table tennis shirts, badminton shirts, runningshirts, football pants, tennis pants, basketball pants, table tennispants, badminton pants, running pants, golf pants, various types ofsporting undershirts, various types of sporting innerwear, sweaters,T-shirts, jerseys, sweat shirts, windbreakers, shorts, leggings, and thelike; products for light incontinence, such as incontinence pads,sanitary napkins, sheets designed to absorb vaginal discharge, such asparty-liners, breastfeeding pads, and the like. The location of thenon-skin-side water-repellent region in the water repellency-impartedfiber article of the present invention can be appropriately setaccording to the use of the water repellency-imparted fiber article. Thelocation of the non-skin-side water-repellent region is set, at least onthe non-skin-facing surface of the fiber article, at a section whereliquid seepage is expected to occur in the intended use, for example, asection corresponding to an excretion part, such as the penis, anarmpit, the back, a crotch portion, the buttocks, or a nipple portion.

An incontinence pad typically includes a topsheet that is disposed at aposition relatively close to the skin of a wearer, a backsheet that isdisposed at a position relatively away from the skin of the wearer, andan absorbent member that is interposed between the topsheet and thebacksheet. When the incontinence pad is worn, the backsheet may comeinto contact with outer clothing such as a pair of trousers.Accordingly, in the case where the water repellency-imparted fiberarticle of the present invention is applied to an incontinence pad, thewater repellency-imparting agent can be applied to an outer surface(non-skin-facing surface) of the backsheet of the pad to form anon-skin-side water-repellent region thereon.

A method for producing the water repellency-imparted fiber article ofthe present invention includes the step of applying a waterrepellency-imparting agent to a non-skin-facing surface of a fiberarticle having the above-described water absorbency, that is, the “waterabsorbency in terms of a water absorption time of 30 seconds or less asmeasured in accordance with the dropping method of JIS L-1907”. Thewater repellency-imparted fiber article of the present invention canbasically be produced simply by performing this step, and therefore canbe efficiently produced without the necessity for a large-sizedequipment or a complicated procedure. Therefore, the method forproducing the water repellency-imparted fiber article of the presentinvention can be performed not only industrially but also privately orin the home.

In the method for producing the water repellency-imparted fiber articleof the present invention, the water repellency-imparting agent need notbe applied to the skin-facing surface of the fiber article, or the waterrepellency-imparting agent may be applied thereto in a smaller amountthan that applied to the non-skin-facing surface of the fiber article,as described above.

There is no particular limitation on the method for applying the waterrepellency-imparting agent to the fiber article. The application meansmay be of a contact type that comes into contact with the fiber articlewhen applying the agent thereto, or of a contactless type that does notcome into contact with the fiber article when applying the agentthereto. As described above, in light of the air permeability, theflexibility, and other properties, the attaching pattern of the waterrepellency-imparting agent in the non-skin-side water-repellent regionis preferably a mixed pattern in which both a portion to which the waterrepellency-imparting agent is attached and a portion to which the waterrepellency-imparting agent is not attached intermingle, rather than apattern in which the water repellency-imparting agent is continuouslypresent over the entire area of the non-skin-side water-repellent regionwhile leaving no gap (such as daubing with the waterrepellency-imparting agent). In view of reliably obtaining such a mixedpattern, it is preferable that, in producing the waterrepellency-imparted fiber article of the present invention, theapplication of the water repellency-imparting agent to the fiber articleis performed by spraying the water repellency-imparting agent with acontactless application means, such as a spray.

Moreover, in the method for producing the water repellency-impartedfiber article of the present invention, the fiber article may be driedafter the water repellency-imparting agent is applied to the fiberarticle. To dry the water repellency-imparting agent, drying may beperformed by heat, vacuum, or combination thereof (forced drying), orair drying may be performed. In the case of drying by heat, it ispreferable that drying be performed without damaging a base material ofthe fiber article and the water repellency-imparting agent. Inparticular, when the water repellency-imparting agent that is applied tothe fiber article is the above-described liquid material containing avolatile solvent and a modified silicone dissolved therein, the volatilesolvent can be reliably removed by introducing the drying step. In thatcase, the conditions for drying the fiber article after the waterrepellency-imparting agent is applied thereto can be appropriately setaccording to the components, including the volatile solvent, of thewater repellency-imparting agent; however, in view of allowing the waterrepellency-imparting agent applied and attached to the fiber article tofully perform its function to thereby achieve both the air permeabilityand the water repellency, as well as in view of preventing dimensionalshrinkage and impregnation with the water repellency-imparting agent,the fiber article is more preferably dried under a condition that thetemperature of the applied water repellency-imparting agent is 50° C. orless.

Examples of the method for applying and attaching the waterrepellency-imparting agent to the fiber article include immersion in asolution, spray coating, dipping, and a roll-on method as well ascoating using a known liquid coating apparatus, including coating thatfollows a printing method such as transfer printing, die coating,gravure coating, inkjet printing, and screen printing. These methods canbe arbitrarily used. Moreover, in the case where the waterrepellency-imparting agent is solidified, the following method can beadopted. Specifically, for example, the water repellency-imparting agentsolidified into a stick shape is brought into direct contact with thefiber article to thereby apply the water repellency-imparting agentthereto, or the water repellency-imparting agent is indirectly appliedto the fiber article using a sponge or the like. Of these methods, spraycoating is preferable because a desired state can be efficientlyprovided by appropriately adjusting the properties, such as viscosity,of the water repellency-imparting agent, the shape of a spray nozzle,the amount of water repellency-imparting agent applied, and otherconditions. In particular, a method in which an aerosol sprayer, amanual trigger sprayer, ultrasonic waves, or the like is used forapplying and attaching the water repellency-imparting agent is morepreferable because the user can form a water-repellent layer in a simpleand easy manner. Moreover, when applying the water repellency-impartingagent, it is necessary to appropriately adjust the conditions in orderto control the penetrability of the agent, including the viscosity ofthe blended composition as the water repellency-imparting agent, thepressure applied to the fiber article such as a fabric cloth, the movingspeed of the sprayer, and the textile printing speed.

An example of the application means that can be used in the productionmethod of the present invention is a pump spray-type application meansin which the water repellency-imparting agent (composition containing amodified silicone) is put into a container equipped with a sprayer. Thatis to say, in the method for producing the water repellency-impartedfiber article of the present invention, the application of the waterrepellency-imparting agent to the fiber article can be performed byspraying the water repellency-imparting agent using a pump spray-typeapplication means. In the present invention, conventionally known pumpspray-type application means can be used without limitation.

Another example of the application means that can be used in theproduction method of the present invention is an aerosol spray-typeapplication means in which the water repellency-imparting agent(composition containing a modified silicone) and a propellant are putinto a pressure-resistant container for aerosol spray. That is to say,in the method for producing the water repellency-imparted fiber articleof the present invention, the application of the waterrepellency-imparting agent to the fiber article can be performed byspraying the water repellency-imparting agent using an aerosolspray-type application means in which the water repellency-impartingagent and a propellant are put into a pressure-resistant container foraerosol spray. In the present invention, conventionally known aerosolspray-type application means can be used without limitation. Examples ofthe propellant include those that use a compressed gas, such as anitrogen gas or a carbonic acid gas, and those that use a liquefied gas,such as a liquefied petroleum gas (LPG) or dimethyl ether (DME).

Still another example of the application means that can be used in theproduction method of the present invention is a manual spray-typeapplication means in which the water repellency-imparting agent(composition containing a modified silicone) is put into a containerequipped with a manual sprayer. That is to say, in the method forproducing the water repellency-imparted fiber article of the presentinvention, the application of the water repellency-imparting agent tothe fiber article can be performed by spraying the waterrepellency-imparting agent using a manual spray-type application meansin which the water repellency-imparting agent is put into a containerequipped with a manual sprayer. Such a manual spray-type applicationmeans is a sprayer that does not use any propellant such as a gas, andspecific examples thereof include a manual trigger sprayer and anultrasonic sprayer. In particular, a manual spray-type application meanswith an accumulator provides favorable small mist particle size,uniformity of mist particle size, and the like, and is suitably used inthe present invention. Moreover, as for one example of the method forusing the manual spray-type application means, the waterrepellency-imparting agent can be sprayed with compressed air or thelike using a container equipped with a compressor.

Moreover, yet another example of the application means that can be usedin the production method of the present invention is an applicationmeans including a stick-shaped solidified matter of the waterrepellency-imparting agent (composition containing a modified silicone),the application means being configured such that the waterrepellency-imparting agent can be applied to an object by bringing thesolidified matter into contact with that object. That is to say, in themethod for producing the water repellency-imparted fiber article of thepresent invention, the application of the water repellency-impartingagent to the fiber article can be performed by using an applicationmeans that includes a stick-shaped solidified matter of the waterrepellency-imparting agent and bringing the solidified matter intocontact with an object. Such an application means including thestick-shaped solidified matter can be configured in the same manner as,for example, lipstick, a glue stick, and the like, and includes thestick-shaped solidified matter of the water repellency-imparting agentand a support portion that supports the solidified matter.

Moreover, yet another example of the agent application means that can beused in the production method of the present invention is a roll-onapplication means in which the water repellency-imparting agent(composition containing a modified silicone) is put into a roll-oncontainer. That is to say, in the method for producing the waterrepellency-imparted fiber article of the present invention, theapplication of the water repellency-imparting agent to the fiber articlecan be performed using a roll-on application means in which the waterrepellency-imparting agent is put into a roll-on container. The roll-oncontainer has, in the opening thereof, an inner stopper in which a ballis freely rotatably held, and is configured to distribute the content(water repellency-imparting agent) over a ball surface and apply thecontent to a desired section. To use the roll-on container, while theball is in contact with the non-skin-facing surface of the fiber articleas an object to which the content is to be applied, the main body of thecontainer is raised up to cause the content to come into contact withthe ball, and the ball is rolled on the non-skin-facing surface tothereby distribute the content over the ball surface. Known roll-oncontainers can be used as the roll-on container without limitation.

Information about the usage method of the application means may beprovided, so that the information is externally visible, on theapplication means that is used to apply the water repellency-impartingagent to the fiber article in the production method of the presentinvention, including the above-described pump spray-type applicationmeans, aerosol spray-type application means, manual spray-typeapplication means, application means including a stick-shaped solidifiedmatter, or roll-on agent application means. In particular, in the casewhere the treatment method according to the present invention isperformed privately or in the home, the user can be effectivelyprevented from incorrectly using the application means and therefore cansmoothly perform the operation for imparting water-repellency to fiberarticle, if information about the application means for use in themethod is provided externally visibly.

The above-described preferred embodiments can be implemented byappropriately selecting the formulation of the waterrepellency-imparting agent, the application method, and otherconditions. For example, in the case where the waterrepellency-imparting agent is a spray formulation, in order toselectively attach the water repellency-imparting agent to thenon-skin-facing surface of the fiber article while maintaining waterabsorbency of the skin-facing surface, which is located on the oppositeside, the following conditions are preferably combined: the ratio of thevolatile solvent to the water repellency-imparting agent and the binderis 80 mass % or less; dimethyl ether, in which a modified silicone candissolve, is used as the spray propellant (gas agent) in an amount of 50mass % or greater; and, furthermore, the amount of spray propellant isset to be one to three times larger than the amount of the main agentcomposed of the water repellency-imparting agent, the binder, and thesolvent. When these conditions are used, the water repellency-impartingagent with high viscosity and quick-drying ability can be attached tothe surface (non-skin-facing surface) of the fiber article. It is alsopreferable to warn the user to keep the spray at a distance of at least15 cm from the object and complete spraying in at most three to-and-fromotions of spraying.

Although the present invention has been described above based onembodiments thereof, the present invention is not limited to theforegoing embodiments, and changes and modifications can be made thereonas appropriate. In relation to the above-described embodiments of thepresent invention, the following additional remarks will be furtherdisclosed.

1. A water repellency-imparted fiber article, comprising:

a fiber article having a skin-facing surface to be disposed on a sidethat is relatively close to the skin of a user during use and anon-skin-facing surface to be disposed on a side that is relatively awayfrom the skin of the user, the fiber article containing awater-absorbent fiber and having water absorbency in terms of a waterabsorption time of 30 seconds or less as measured in accordance with thedropping method of JIS L-1907; and

a water repellency-imparting agent attached to the fiber article,

wherein the water repellency-imparted fiber article has a non-skin-sidewater-repellent region on the non-skin-facing surface of the fiberarticle, the non-skin-side water-repellent region including a portion towhich the water repellency-imparting agent is attached,

the water repellency-imparted fiber article has a water absorbing layerin a section of the fiber article that overlaps the non-skin-sidewater-repellent region in a plan view and on a side that is closer tothe skin of the user than the non-skin-side water-repellent region, thewater absorbing layer maintaining the water absorbency, and

a surface of the non-skin-side water-repellent region has a watercontact angle of 80 degrees or greater and a water absorption rate of 10seconds or greater.

2. The water repellency-imparted fiber article as set forth in clause 1,wherein both a portion to which the water repellency-imparting agent isattached and a portion to which the water repellency-imparting agent isnot attached are present in the non-skin-side water-repellent region.3. The water repellency-imparted fiber article as set forth in clause 1or 2, wherein in a 50-mm-square region arbitrarily selected from thenon-skin-side water-repellent region, a percentage of the total area ofa portion to which the water repellency-imparting agent is attached tothe whole area of the 50-mm-square region is from 10% to 80%.4. The water repellency-imparted fiber article as set forth in any oneof clauses 1 to 3, wherein a thickness of a portion to which the waterrepellency-imparting agent is attached, of the non-skin-sidewater-repellent region is from 5% to 60% of a thickness of the fiberarticle.5. The water repellency-imparted fiber article as set forth in any oneof clauses 1 to 4, wherein a thickness of a portion to which the waterrepellency-imparting agent is attached, of the non-skin-sidewater-repellent region is from 50% to 60% of a thickness of the fiberarticle.6. The water repellency-imparted fiber article as set forth in any oneof clauses 1 to 5, wherein an air permeance of a section where thenon-skin-side water-repellent region is formed is from 2 seconds/100 mlto 30 seconds/100 ml.7. The water repellency-imparted fiber article as set forth in any oneof clauses 1 to 6, wherein a bending resistance of a section where thenon-skin-side water-repellent region is formed is 60 mm or less, and isequal to or lower than the bending resistance of a section of the waterrepellency-imparted fiber article where the non-skin-sidewater-repellent region is not formed, which is a water-repellent regionnon-formed portion.8. The water repellency-imparted fiber article as set forth in any oneof clauses 1 to 7, wherein an amount of the water repellency-impartingagent attached decreases from the non-skin-facing surface of the fiberarticle toward the skin-facing surface thereof.9. The water repellency-imparted fiber article as set forth in any oneof clauses 1 to 8, wherein the water repellency-imparted fiber articlehas a skin-side water-repellent region on the skin-facing surface of thefiber article, the skin-side water-repellent region including a portionto which the water repellency-imparting agent is attached, and an amountof the water repellency-imparting agent attached in the skin-sidewater-repellent region is smaller than that in the non-skin-sidewater-repellent region.10. The water repellency-imparted fiber article as set forth in any oneof clauses 1 to 9, wherein the non-skin-facing surface of the fiberarticle has an uneven structure, and the water repellency-impartingagent that forms the non-skin-side water-repellent region is attached toprojections constituting the uneven structure.11. The water repellency-imparted fiber article as set forth in any oneof clauses 1 to 9, wherein the water repellency-imparting agent is acomposition containing a modified silicone.12. The water repellency-imparted fiber article as set forth in clause11, wherein the water repellency-imparting agent contains a volatilesolvent in which the modified silicone is soluble.13. The water repellency-imparted fiber article as set forth in clause11 or 12, wherein the composition contains a water-soluble binder.14. The water repellency-imparted fiber article as set forth in any oneof clauses 1 to 13, wherein, when the water repellency-imparted fiberarticle is washed by immersing the water repellency-imparted fiberarticle in a liquid containing 0.1 mass % of a commonly availabledetergent for clothing and ion exchanged water under stirring at arotational speed of 350 rpm for 10 minutes, and then lightly squeezingthe water repellency-imparted fiber article, and further immersing thewater repellency-imparted fiber article in ion exchanged water understirring at a rotational speed of 350 rpm for 10 minutes, an amount ofthe water repellency-imparting agent contained in the waterrepellency-imparted fiber article after washing is 20 mass % or lessbased on that before washing.15. The water repellency-imparted fiber article as set forth in any oneof clauses 1 to 14, wherein the fiber article contains a natural fiberand a synthetic fiber as constituent fibers thereof.16. The water repellency-imparted fiber article as set forth in any oneof clauses 1 to 14, wherein the fiber article contains only a naturalfiber as a constituent fiber thereof.17. The water repellency-imparted fiber article as set forth in any oneof clauses 1 to 16, wherein the water repellency-imparted fiber articlecontains at least one selected from the group consisting of adeodorizing ingredient, an odor-removing ingredient, a fragrantingredient, a antimicrobial agent, a bactericidal agent, and arefreshing agent.18. The water repellency-imparted fiber article as set forth in any oneof clauses 1 to 17, wherein the fiber article is a piece of innerclothing.19. The water repellency-imparted fiber article as set forth in any oneof clauses 1 to 17, wherein the fiber article a piece of sportingclothing.20. The water repellency-imparted fiber article as set forth in any oneof clauses 1 to 17, wherein the fiber article is an incontinence pad.21. A method for producing the water repellency-imparted fiber articleas set forth in any one of clauses 1 to 20, the method comprising:

applying a water repellency-imparting agent to a non-skin-facing surfaceof a fiber article having water absorbency in terms of a waterabsorption time of 30 seconds or less as measured in accordance with thedropping method of JIS L-1907.

22. The method for producing the water repellency-imparted fiber articleas set forth in clause 21, wherein after the water repellency-impartingagent is applied to the fiber article, the fiber article is dried undera condition that a temperature of the water repellency-imparting agentis 50° C. or less.23. The method for producing the water repellency-imparted fiber articleas set forth in clause 21 or 22, wherein the application of the waterrepellency-imparting agent to the fiber article is performed by sprayingthe water repellency-imparting agent.24. The method for producing the fiber article as set forth in any oneof clauses 21 to 23, wherein the application of the waterrepellency-imparting agent to the fiber article is performed by sprayingthe water repellency-imparting agent with a pump spray-type applicationmeans in which the water repellency-imparting agent is put into acontainer equipped with a sprayer.25. The method for producing the fiber article as set forth in any oneof clauses 21 to 24, wherein the application of the waterrepellency-imparting agent to the fiber article is performed by sprayingthe water repellency-imparting agent with an aerosol spray-typeapplication means in which the water repellency-imparting agent and apropellant are put into a pressure-resistant container for aerosolspray.26. The method for producing the fiber article as set forth in any oneof clauses 21 to 24, wherein the application of the waterrepellency-imparting agent to the fiber article is performed by sprayingthe water repellency-imparting agent with a manual spray-typeapplication means in which the water repellency-imparting agent is putinto a container equipped with a manual sprayer.27. The method for producing the fiber article as set forth in any oneof clauses 21 to 23, wherein the application of the waterrepellency-imparting agent to the fiber article is performed with anapplication means including a stick-shaped solidified matter of thewater repellency-imparting agent, the solidified matter being broughtinto contact with the fiber article as an object.28. The method for producing the fiber article as set forth in clause 21or 22, wherein the application of the water repellency-imparting agentto the fiber article is performed with a roll-on application means inwhich the water repellency-imparting agent is put into a roll-oncontainer.29. The method for producing the fiber article as set forth in any oneof clauses 21 to 28, wherein an application means is used for applyingthe water repellency-imparting agent to the fiber article, andinformation about a usage method of the application means is providedsuch that the information is externally visible.

EXAMPLES

Hereinafter, the present invention will be described in greater detailby way of Examples. However, the present invention is not limitedthereto.

Composition A as Water Repellency-Imparting Agent

A polyoxazoline modified silicone (silicone: 75 mass %, polyoxazoline:25 mass %, see JP HS-25025A etc.) as an active of a waterrepellency-imparting agent was dissolved in an ethanol solvent at normaltemperature to obtain a 20 mass % solution in ethanol, and the solutionwas then filled in a spray can together with a dimethyl ether/LPG(70/30) gas (weight ratio of ethanol solution/gas=40/60) to obtaincomposition A as a water repellency-imparting agent in the form of aspray.

Composition B as Water Repellency-Imparting Agent

A polyether modified silicone (trade name “SH-3775M” manufactured by DowCorning Toray Co., Ltd.) serving as an active of a waterrepellency-imparting agent, a (vinyl methyl ether/butyl maleate)copolymer (trade name “Gantrez ES-425” available from Matsumoto TradingCo., Ltd.) serving as a water-soluble binder, and ethanol were mixed ata mass ratio of 10/10/80 and forcibly stirred. The resultant solutionwas filled in a spray can together with a dimethyl ether/LPG (70/30) gas(weight ratio of ethanol solution/gas=40/60) to obtain composition B asa water repellency-imparting agent in the form of a spray. The dispersedstate of composition B was unstable, and therefore, the spray can wasshaken several time before use.

Composition C as Water Repellency-Imparting Agent

A commercially-available spray-type water repellency-imparting agent(trade name “Scotchgard for clothes and fabric products” manufactured by3M) was used as composition C as a water repellency-imparting agentas-is.

Fiber Article I: Pre-treated Cotton Fabric

A raw fabric (oxford plain white cotton fabric, product number:2012200003154, purchased at Yuzawaya) with a width of 60 cm, a length of1 m, and a basis weight of 180 g/m² was provided. The raw fabric waspre-treated for the purpose of eliminating the effects of a process oiland the like. Specifically, the raw fabric was washed and rinsed, anddried for twenty-four hours in an environment of 23±2° C./50±5% RH.After that, the raw fabric was ironed at a high temperature with use ofan iron (NI-S33 manufactured by Panasonic Corporation) to removewrinkles. The washing and rinsing were performed using acommercially-available washing machine (NW-500MX manufactured byHitachi, Ltd.) and 30 g of a commercially-available detergent (UltraAttack Neo manufactured by Kao Corporation) with 30 L of water, throughthe following process “washing for 4 minutes→a single rinsecycle→spinning for 5 minutes”. The pre-treated cotton fabric thusobtained was used as fiber article I. Fiber article I had waterabsorbency in terms of a water absorption time of 30 seconds or less asmeasured in accordance with the dropping method of JIS L-1907.

Example 1

Fiber article I (the pre-treated cotton fabric) having a 10 cm×10 cmsquare shape in a plan view was placed on top of filter paper with oneside thereof facing upward. A water repellency-imparting agent wasapplied onto the entire upper surface of fiber article I using a spray(with a pressure of 0.4 mPa) that was positioned at 25 cm above fiberarticle I for a spray duration time of 2 seconds. Then, fiber article Iwas allowed to stand for 30 minutes to dry. In this manner, awater-repellent region including a portion to which the waterrepellency-imparting agent was attached was formed over the entiresurface on one side of fiber article I, to thereby obtain a waterrepellency-imparted fiber article. The areal weight of the waterrepellency-imparting agent in the obtained water repellency-impartedfiber article was 0.15 g/m² in terms of solid content. Composition A wasused as the water repellency-imparting agent.

Example 2

A water repellency-imparted fiber article was obtained in the samemanner as in Example 1, except that the spray duration time for applyingthe water repellency-imparting agent with the spray was 10 seconds. Theareal weight of the water repellency-imparting agent in the obtainedwater repellency-imparted fiber article was 1.10 g/m² in terms of solidcontent.

Example 3

A water repellency-imparted fiber article was obtained in the samemanner as in Example 1, except the following: composition B was used asthe water repellency-imparting agent, fiber article I was dried (allowedto stand) for 5 minutes after spraying of the water repellency-impartingagent, and the following post-treatment (esterification treatment) wasperformed after drying. The areal weight of the waterrepellency-imparting agent in the obtained water repellency-impartedfiber article was 0.10 g/m² in terms of solid content.

Post-Treatment after Application of Water Repellency-Imparting Agent

The entire upper surface of the fiber article to which the waterrepellency-imparting agent was attached was covered with a press cloth(white broadcloth cotton fabric, product number: 2012200092448,purchased at Yuzawaya), and ironed over the press cloth at a lowtemperature with an iron (NI-S33 manufactured by Panasonic Corporation).Then, the fiber article was allowed to stand for 20 minutes. During thisironing at a low temperature, ironing was performed such that thetemperature of the surface (upper surface) of the fiber article to whichthe water repellency-imparting agent was attached was 50° C.

Comparative Example 1

A water repellency-imparted fiber article was obtained in the samemanner as in Example 1, except that composition C was used as the waterrepellency-imparting agent. The areal weight of the waterrepellency-imparting agent in the obtained water repellency-impartedfiber article was 0.10 g/m² in terms of solid content.

Comparative Example 2

Fiber article I (i.e., the pre-treated cotton fabric), which was anintermediate product for Example 1, was used as Comparative Example 2as-is.

Comparative Example 3

A water repellency-imparted fiber article was obtained in the samemanner as in Example 1, except that the spray duration time for applyingthe water repellency-imparting agent (composition A) with the spray was0.8 seconds. The areal weight of the water repellency-imparting agent inthe obtained water repellency-imparted fiber article was 0.04 g/m² interms of solid content.

Comparative Example 4

A water repellency-imparted fiber article was obtained in the samemanner as in Example 1, except that the spray duration time for applyingthe water repellency-imparting agent (composition A) with the spray was3.5 seconds. The areal weight of the water repellency-imparting agent inthe obtained water repellency-imparted fiber article was 0.29 g/m² interms of solid content.

Performance Evaluation I

On the fiber articles (water repellency-imparted fiber articles) ofExamples and Comparative Examples, in which fiber article I was used asthe base, the contact angle and the water repellency angle (slidingangle) on various portions, the water absorption rate, the occupancyratio of portions to which the water repellency imparting agent wasattached, the thickness ratio of the water repellency-imparting agent,the air permeance, the bending resistance, and other properties weredetermined in accordance with the above-described methods, and a tactilefeel test, which will be described later, was also performed. Table 1below shows the results. For a single sample, each of thesedeterminations was performed five times at different observationpositions, and an average of the five found values was used as arepresentative value for that sample. Moreover, the samples of Examplesand Comparative Examples were subjected to a seepage test and a usagetest, which will be described later. Table 2 below shows the results.

1. Tactile Feel Test

Five male panelists to touch with their fingers the entirety of eachtest sample having a 100 mm×100 mm quadrangular shape in a plan view,and evaluated the overall tactile sensation and the softness at thattime in accordance with the following evaluation criteria. The averageof evaluation scores made by the five panelists was used as theevaluation result of the test sample. The higher the evaluation scorewas, the higher the evaluation was.

Evaluation Criteria for Overall Tactile Sensation

1 point: Poor, 2 points: Slightly poor, 3 points: Fair, 4 points:Slightly good, 5 points: Good

Evaluation Criteria for Softness

1 point: Hard, 2 points: Slightly hard, 3 points: Fair, 4 points:Slightly soft, 5 points: Soft

2. Seepage Test

Filter paper and a water-permeable sheet were laid one on top of theother in that order on a horizontal stage, and were allowed to stand for2 hours in an environment at a temperature of 25° C. A fiber article towhich no water repellency-imparting agent was applied, that is, theabove-described pre-treated cotton fabric was used as thewater-permeable sheet. Next, a fiber article (any one of Examples andComparative Examples) as a test sample was laid on the water-permeablesheet. At that time, in the case where the test sample was fiber articlein which the water repellency-imparting agent was applied to one sidethereof, the test sample was laid on the water-permeable sheet such thatthe side to which the water repellency-imparting agent was applied facedthe water-permeable sheet. Then, 1 mL of blue water was dropped onto theupper surface of the test sample with a dropper. The blue water wasprepared by coloring distilled water with a coloring agent (Blue No. 1)(the content of the coloring agent in the blue water was 0.1 mass %). 5minutes after the dropping of the blue water, the test sample wasremoved, and the remaining lower fabric and filter paper were eachvisually observed, and evaluated in accordance with the followingevaluation criteria. In the present test, the test sample and thewater-permeable sheet were regarded as a piece of inner clothing such asunderwear, and a piece of outer clothing, respectively, and the seepageof a liquid (blue water) from the test sample side to thewater-permeable-sheet side was evaluated.

Evaluation Criteria for Seepage

Very good: Any portion to which the blue water was attached were notpresent both in the water-permeable sheet and in the filter paper.

Good: A portion to which the blue water was attached, the portion havinga dot-like shape in a plan view and a maximum diameter of 5 mm or less,was present in the water-permeable sheet, but any portion to which theblue water was attached were not present in the filter paper.

Poor: A relatively large portion (so-called stain) to which the bluewater was attached and which had a maximum diameter of greater than 20mm was present in the water-permeable sheet, but any portion to whichthe blue water were not attached was present in the filter paper.

Very poor: A portion to which the blue water was attached and which atleast had a diameter of 2 mm or greater was observed in the filterpaper; or a relatively large portion (so-called stain) to which the bluewater was attached and which had a maximum diameter of greater than 40mm was present in the water-permeable sheet, and a portion to which theblue water was attached was present in the filter paper.

On the sample of Example 1, an additional seepage test was performed, inaddition to the above-described seepage test. In the additional seepagetest, the same procedure as of the above-described seepage test wasperformed, except that the water-permeable sheet and the evaluationsample were replaced by each other. In this additional seepage test, thewater-permeable sheet and the test sample were regarded as a piece ofinner clothing such as underwear and a piece of outer clothing,respectively, and the seepage of a liquid (blue water) from thewater-permeable-sheet side to the test sample side was evaluated. InTable 2 below, the above-described seepage test is indicated by“Suitability for inner clothing”, the additional seepage test isindicated by “Suitability for outer clothing”, and the two tests arethereby differentiated from each other.

3. Usage Test (Pants)

Two men who were conscious of the occurrence of so-called“after-dribble” at least once a day served as panelists. Each of the twopanelists were given 100% cotton underpants (inner clothing) of a typehe usually uses, as well as compositions A to C (each in the form of aspray) as the water repellency-imparting agent. The panelists wereinstructed to spray any one of the compositions on the non-skin-facingsurface side of the underpants, dry the underpants for one day, thenwear the resulting underpants and trousers (jeans), which are outerclothing, on the underpants, and go about their lives as usual in thatstate. The test period was two days for each water repellency-impartingagent, and if the underpants were soiled due to after-dribble or thelike, the underpants were replaced every time with a new pair ofunderpants on which the water repellency-imparting agent was sprayed.During the test period, the panelists made sensory evaluations of (1-1)the number of times urine seeped into the trousers due to after-dribble,(1-2) the result of the occurrence of after-dribble, (1-3) the overallevaluation of the underpants, and (1-4) the wearing comfort of theunderpants. The average of the evaluations made by the two panelists wasused as the evaluation result with respect to the test sample.

With regard to item (1-1), when after-dribble occurred in a panelist,the panelist visually observed the trousers from outside. If a urinestain in the trousers was found, the number of times urine seeped intothe trousers was one, and if no urine stain was found in the trousers,the number of times urine seeped into the trousers was zero. It can bedetermined that as the number of times urine seeped into the trouserswas smaller, the seepage-suppressing effect of the underpants to whichthe water repellency-imparting agent was attached (waterrepellency-imparted fiber article) was more significant and thus highlyrated.

With regard to item (1-2), the result of the occurrence of after-dribblerefers to matters that the panelist actually perceived whenafter-dribble occurred in that panelist, and if the panelist did notperceive urine seeping into the trousers side, the “seepage into thetrousers was prevented”, which was highly rated. Otherwise, the panelistreported the specific result, and for example, the panelist reported asfollows: urine passed through the underpants and transferred to thetrousers side; urine flowed out from the bottom of the underpants; andso on.

With regard to item (1-3), the panelists made overall evaluation of theunderpants, in comparison with the same type of underpants that theyusually wear, on a five-point scale with consideration given to therelief and the like when wearing the underpants. As the evaluation scorewas higher, the test sample was highly rated.

1 point: Poor, 2 points: Slightly poor, 3 points: Equivalent, 4 points:Slightly good, 5 points: Good

With regard to item (1-4), the panelists evaluated the stiff feel(hardness), in comparison with the same type of underpants that theyusually wear, on the following five-point scale. As the evaluation scorewas higher, the test sample was more highly rated.

1 point: Feel stiff, 2 points: Feel slightly stiff, 3 points: Neither, 4points: Feel slightly not stiff, 5 points: Feel not stiff

TABLE 1 Examples Comparative Examples 1 2 3 1 2 3 4 Waterrepellency-imparting agent A A B C — A A Amount of waterrepellency-imparting agent attached    0.15 1.10    0.10 0.10 0 0.040.29 (g/m²) Occupancy ratio of portion to which water repellency- 45 6845 89 0 9 88 imparting agent is attached (%) Thickness ratio of waterrepellency-imparting agent (%) 60 55 50 95 0 38 67 Air permeance (sec.)17 22 17 32 15 16 35 Water contact angle on surface to which water 90 9885 100 N.D. *1 N.D. *1 100 repellency-imparting agent is applied (°)Water contact angle on surface to which water N.D. *1 60 N.D. *1 100N.D. *1 N.D. *1 90 repellency-imparting agent is not applied (°) Waterrepellency angle on surface to which water 30 10 40 10 80 80 10repellency-imparting agent is applied (°) Water repellency angle onsurface to which water N.D. 60 N.D. 10 80 80 15 repellency-impartingagent is not applied (°) Water absorption rate of surface to which water50 60 sec.≤ 40 60 sec.≤ Instant*2 Instant*2 60 sec.≤repellency-imparting agent is applied (sec.) Water absorption rate ofsurface to which water Instant*2 7 Instant*2 60 sec.≤ Instant*2Instant*2 40 repellency-imparting agent is not applied (sec.) Bendingresistance (mm) 40 50 55 65 50 50 35 Tactile feel test Overall tactilesensation (points)   5.0 5.0   4.2 2.4 4.4 5.0 2.0 Softness (points)  5.0 5.0   4.0 2.4 4.4 5.0 5.0 *1: The liquid drop used indetermination was instantly absorbed, and thus determination wasimpossible. *2The water absorption rate was too fast to be determined,and thus determination was impossible.

TABLE 2 Examples Comparative Examples 1 2 3 1 Water repellency-impartingagent A A B C Amount of water repellency-imparting agent attached   0.15 1.10    0.10 0.10 (g/m²) Occupancy ratio of portion to whichwater repellency- 45 68 45 89 imparting agent is attached (%) Thicknessratio of water repellency-imparting agent (%) 60 55 50 95 Air permeance(sec.) 17 22 17 32 Water contact angle on surface to which water 90 9885 100 repellency-imparting agent is applied (°) Water contact angle onsurface to which water N.D. *1 60 N.D. *1 100 repellency-imparting agentis not applied (°) Water repellency angle on surface to which water 3010 40 10 repellency-imparting agent is applied (°) Water repellencyangle on surface to which water N.D. 60 N.D. 10 repellency-impartingagent is not applied (°) Water absorption rate of surface to which water50 60 sec.≤ 40 60 sec.≤ repellency-imparting agent is applied (sec.)Water absorption rate of surface to which water Instant*2 7 Instant*2 60sec.≤ repellency-imparting agent is not applied (sec.) Bendingresistance (mm) 40 50 55 65 Seepage test Suitability for inner clothingVery good Very good Very good Very poor Suitability for outer clothingVery good — — — Usage test Number of times urine seeped into  0 0  0 2trousers (times) Result of occurrence of after-dribble Seepage of urineSeepage of urine Seepage of urine Every time into trousers into trousersinto trousers after-dribble was prevented. was prevented. was prevented.occurred, urine flowed inside underpants and seeped into trousers frombottom of underpants. Overall evaluation (points)   5.0 5.0   4.0 2.5Wearing comfort (points)   5.0 5.0   4.0 2.5 Comparative Examples 2 3 4Water repellency-imparting agent — A A Amount of waterrepellency-imparting agent attached  0    0.04 0.29 (g/m²) Occupancyratio of portion to which water repellency-  0  9 88 imparting agent isattached (%) Thickness ratio of water repellency-imparting agent (%)  038 67 Air permeance (sec.) 15 16 35 Water contact angle on surface towhich water N.D. *1 N.D. *1 100 repellency-imparting agent is applied(°) Water contact angle on surface to which water N.D. *1 N.D. *1 90repellency-imparting agent is not applied (°) Water repellency angle onsurface to which water 80 80 10 repellency-imparting agent is applied(°) Water repellency angle on surface to which water 80 80 15repellency-imparting agent is not applied (°) Water absorption rate ofsurface to which water Instant*2 Instant*2 60 sec.≤ repellency-impartingagent is applied (sec.) Water absorption rate of surface to which waterInstant*2 Instant*2 40 repellency-imparting agent is not applied (sec.)Bending resistance (mm) 50 50 35 Seepage test Suitability for innerclothing Very poor Very poor Very poor Suitability for outer clothing —— — Usage test Number of times urine seeped into  2  2 2 trousers(times) Result of occurrence of after-dribble Every time Every timeEvery time after-dribble after-dribble after-dribble occurred, urineoccurred, urine occurred, urine passed through passed through flowedinside underpants and underpants and underpants and seeped into seepedinto seeped into trousers. trousers. trousers from bottom of underpants.Overall evaluation (points)   2.0   2.0 2.0 Wearing comfort (points)  4.0   2.0 2.0 *1: The liquid drop used in determination was instantlyabsorbed, and thus determination was impossible. *2The water absorptionrate was too fast to be determined, and thus determination wasimpossible.

As shown in Tables 1 and 2, in all of the fiber articles of Examples,which were water repellency-imparted fiber articles in which the waterrepellency-imparting agent was applied to the entire surface on one sidethereof, the surface to which the water repellency-imparting agent wasapplied (surface of water-repellent region) had a water contact angle of80 degrees or greater (water repellency angle of 40 degrees or less) anda water absorption rate of 10 seconds or greater, and also, the surfaceto which the water repellency-imparting agent was not applied and whichwas located on the opposite side to the surface to which the waterrepellency-imparting agent was applied exhibited high water absorbencysuch that the water contact angle was 60 degrees or less, or such thatthe water repellency angle was 50 degrees or greater, or such that thecontact angle was not able to be measured. Thus, it can be determinedthat all the fiber articles of Examples had a water absorbing layermaintaining the “water absorbency in terms of a water absorption time of30 seconds or less as measured in accordance with the dropping method ofJIS L-1907”, the water absorbing layer being located on the side thatwas closer to the skin of the user than the non-skin-sidewater-repellent region including the portion to which the waterrepellency-imparting agent composition was attached. Therefore, all thefiber articles of Examples exhibited the excellent effect of preventingof bodily fluid seepage, compared with Comparative Examples. Moreover,from the favorable results of the usage test, it can be seen that thefiber articles of Examples can be effective in addressing after-dribblewhen actually used for underpants. Furthermore, even though the fiberarticles of Example had water-repellency, those fiber articles had highair permeance and were less likely to cause dampness, compared withComparative Examples 1 and 4, which were the fiber articles that hadwater-repellency as well. In addition, the results of the tactile feeltest of Examples were equal to or better than those of ComparativeExample 2, which was the fiber article that was not madewater-repellent. Therefore, it is clear that, according to the presentinvention exemplified by Examples, bodily fluid seepage, specifically,urine seepage due to after-dribble, or the like can be effectivelyprevented without impairing the texture of the fiber article.

Unlike Comparative Example 2, the fiber article of Comparative Example 1had water-repellency through the application of the waterrepellency-imparting agent; however, the surface thereof to which thewater repellency-imparting agent was not applied had a water contactangle of 60 degrees or greater (water repellency angle of less than 50degrees), and it is therefore considered that this fiber article did nothave a water absorbing layer that maintained the above-described waterabsorbency, on the side that was closer to the skin of the user than thenon-skin-side water-repellent region including the portion to which thewater repellency-imparting agent was attached. In other words, thisfiber article was made water-repellent over the entire area in thethickness direction thereof, and thus, the intrinsic water absorbencythereof was significantly impaired. It is inferred that, for thisreason, the results of the seepage test were poor, and that, in theusage test, urine flowed down on the inner side of the underwear whenafter-dribble occurred, which resulted in an extremely poor usage feeland failure in prevention of seepage.

The fiber article of Comparative Example 3 had water-repellency throughthe application of the water repellency-imparting agent. However, thethickness ratio of the water repellency-imparting agent was not within asuitable range, that is, not within a range of 50 to 60%, which was therange of Examples 1 to 3, and specifically, the thickness ratio of thewater repellency-imparting agent was 38%, which was excessively low.Accordingly, the function of the non-skin-side water-repellent region asa barrier layer was insufficient, and it is inferred that, for thisreason, the results of the seepage test and the usage test were poor. Onthe other hand, the fiber article of Comparative Example 4 had athickness ratio of the water repellency-imparting agent of 67%, whichwas excessively high. Accordingly, as is the case with ComparativeExample 1, the intrinsic water absorbency of the underwear, which waslocated on the skin-facing surface side, was not sufficiently used, andit is thought that, for this reason, every time after-dribble occurred,urine flowed down on the inner side of the underwear to cause seepageand impair the usage feel significantly. Moreover, due to the effect ofthe excessive amount of water repellency-imparting agent, the numericalvalue of the air permeance was high, which was detrimental to the airpermeability, and, in addition, the difference in the numerical value ofthe bending resistance from that of Comparative Example 2, to which thewater repellency-imparting agent composition was not applied, wasconsiderable, which means that the fiber article was excessivelyflexible and was also sticky to the touch. It is inferred that, for thisreason, the result with respect to the overall tactile sensation waspoor. Composition A as a water repellency-imparting agent used inComparative Example 4 was a type of modified silicone-containing waterrepellency-imparting agent which has been described above, and had aproperty such that the flexibility of the section to which the agent isattached more increased (the stiffness of that section more decreased)as the amount of the agent attached was larger.

Fiber Article II: Inner Shirt

A commercially-available 100% cotton inner shirt (YG V neck from GunzeLimited, product number: 31YV0015N) was used as fiber article II as-is.Fiber article II had water absorbency in terms of a water absorptiontime of 30 seconds or less as measured in accordance with the droppingmethod of MS L-1907.

Example 4

Fiber article II (inner shirt) was placed on filter paper with the outersurface (non-skin-facing surface) on the back side thereof facingupward. A water repellency-imparting agent was applied onto the centralportion of the back-side outer surface of fiber article II using a spray(with a pressure of 0.4 mPa) that was positioned at 25 cm above fiberarticle II. Then, fiber article II was allowed to stand to dry. Duringspraying, the water repellency-imparting agent was sprayed over a regionhaving a rectangular shape in a plan view with a length of 20 cm and awidth of 30 cn. The water repellency-imparting agent was sprayed for 10seconds, and was uniformly sprayed over the rectangular region entirelyso that the water repellency-imparting agent was prevented fromaccumulating at one portion on fiber article II. The drying afterspraying was performed by allowing fiber article II to which the waterrepellency-imparting agent was applied to stand for twenty-four hours inan environment at room temperature (environment at 23±2° C./50±5% RH).The areal weight of the water repellency-imparting agent in the obtainedwater repellency-imparted fiber article was 0.10 g/m² in terms of solidcontent. Composition A was used as the water repellency-imparting agent.

Comparative Example 5

A water repellency-imparted fiber article was obtained in the samemanner as in Example 4, except that composition C was used as the waterrepellency-imparting agent. The areal weight of the waterrepellency-imparting agent in the obtained water repellency-impartedfiber article was 0.10 g/m² in terms of solid content.

Comparative Example 6

Fiber article II, which was an intermediate product for Example 4, thatis, the commercially-available cotton shirt was used as ComparativeExample 6 as-is.

Performance Evaluation II

On the fiber articles (water repellency-imparted fiber articles), inwhich fiber article II was used as the base, of Example and ComparativeExamples, the contact angle and the water repellency angle (slidingangle) on various portions, the water absorption rate, the occupancyratio of portions to which the water repellency imparting agent wasattached, the thickness ratio of the water repellency-imparting agent,the air permeance, the bending resistance, and other properties weredetermined in accordance with the above-described methods, and theabove-described tactile feel test was also performed. Table 3 belowshows the results. For a single sample, each of these determinations wasperformed five times at different observation positions, and an averageof the five found values was used as a representative value for thatsample. Moreover, the samples of Example and Comparative Examples weresubjected to the above-described seepage test, and a usage test below.Table 4 below shows the results.

Usage Test (Inner Shirt)

Each of two male panelists was given following items: six,commercially-available 100% cotton inner shirts (YG V neck from GunzeLimited, product number: 31YV0015N) as pieces of inner clothing, theinner shirts being the right size for the panelist; compositions A and C(each in the form of a spray) as the water repellency-imparting agent;and two commercially-available polo shirts (UNIQLO dry pique poloshirts, short-sleeve, gray, product number: 180719, 72% cotton, 28%polyester) as pieces of outer clothing to be worn directly on the innershirts, the polo shirts being the right size for the panelist. Thepanelists wore the inner shirt after spraying a waterrepellency-imparting agent onto the central portion of the back-sideouter surface of the inner shirt and drying the inner shirt. Withrespect to spraying and drying, the panelists were instructed to spraythe water repellency-imparting agent onto a region having a rectangularshape in a plan view with a length of 20 cm and a width of 30 cm for aspraying time of 10 seconds. Furthermore, the panelists were instructedto spray the water repellency-imparting agent uniformly over therectangular region entirely so that the water repellency-imparting agentwas prevented from accumulating at one portion on the inner shirt, andalso instructed to dry the inner shirt after spraying at roomtemperature for twenty-four hours before wearing. Furthermore, thepanelists were instructed to wear the outer clothing (polo shirt)directly on the sprayed and dried inner shirt, and go about their livesas usual in this state. The test period was two days for each waterrepellency-imparting agent, and the outer clothing was washed every dayand worn. During the test period, the panelists made sensory evaluationsof (2-1) the number of times sweat seeped into the back of the outerclothing due to sweating, (2-2) the result of sweat staining, (2-3) theoverall evaluation of the inner shirts, and (2-4) the wearing comfort ofthe inner shirts. The average of the evaluations made by the twopanelists was used as the evaluation result with respect to the relevanttest sample.

With regard to item (2-1), the panelists went about their lives asusual, and visually observed their backs in a mirror at about twoo'clock p.m. every day. If a sweat stain in the outer clothing wasfound, the number of times sweat seepage occurred was one, and if nosweat stain in the outer clothing was found, the number of times sweatseepage occurred was zero. It can be determined that, as the number ofsweat seepage occurred was smaller, the seepage-suppressing effect ofthe inner shirt (water repellency-imparted fiber article) to which thewater repellency-imparting agent was attached was more significant andthus highly rated.

With regard to item (2-2), the result of sweat staining refers to thematters that the panelist felt when observing their backs to evaluateitem (2-1), and if seepage into the outer clothing did not occur, the“seepage into the outer clothing was prevented”, which was highly rated.Otherwise, the panelist reported the specific result, and for example,the panelist reported as follows: sweat passed through the inner shirtand transferred to the outer clothing side; sweat dripped down theregion to which the water repellency-imparting agent was sprayed,causing a statin in a portion below that region or causing dampness; andso on.

With regard to item (2-3), the panelists made overall evaluation of theinner shirts, in comparison with the same type of inner shirts that theyusually wear, on a five-point scale with consideration given to therelief and the like when wearing the inner shirts. As the evaluationscore was higher, the test sample was highly rated.

1 point: Poor, 2 points: Slightly poor, 3 points: Equivalent, 4 points:Slightly good, 5 points: Good

With regard to item (2-4), the panelists evaluated the wearing comfortin terms of a damp feel, stickiness, a stiff feel (hardness), and thelike, in comparison with the same type of inner shirts that they usuallywear, on the following five-point scale. As the evaluation score washigher, the test sample was more highly rated

1 point: Poor, 2 points: Slightly poor, 3 points: Equivalent, 4 points:Slightly good, 5 points: Good

TABLE 3 Example Comparative Examples 4 5 6 Water repellency-impartingagent A C — Amount of water repellency- 0.10 0.10 0 imparting agentattached (g/m²) Occupancy ratio of portion to which 45 89 0 waterrepellency-imparting agent is attached (%) Thickness ratio of waterrepellency- 60 95 0 imparting agent (%) Air permeance (sec.) 17 32 15Water contact angle on surface to 90 100 N.D.*1 which waterrepellency-imparting agent is applied (°) Water contact angle on surfaceto N.D.*1 100 N.D.*1 which water repellency-imparting agent is notapplied (°) Water repellency angle on surface to 30 10 80 which waterrepellency-imparting agent is applied (°) Water repellency angle onsurface to N.D. 10 80 which water repellency-imparting agent is notapplied (°) Water absorption rate of surface to 50 60 sec.≤ Instant*2which water repellency-imparting agent is applied (sec.) Waterabsorption rate of surface to Instant*2 60 sec.≤ Instant*2 which waterrepellency-imparting agent is not applied (sec.) Bending resistance (mm)40 65 50 Tactile feel Overall tactile 5.0 2.4 4.4 test sensation(points) Softness (points) 5.0 2.4 4.4 *1The liquid drop used indetermination was instantly absorbed, and thus determination wasimpossible. *2The water absorption rate was too fast to be determined,and thus determination was impossible.

TABLE 4 Example Comparative Examples 4 5 6 Water repellency-impartingagent A C — Amount of water repellency-imparting    0.10 0.10  0 agentattached (g/m²) Occupancy ratio of portion to which 45 89  0 waterrepellency-imparting agent is attached (%) Thickness ratio of water 6095  0 repellency-imparting agent (%) Air permeance (sec.) 17 32 15 Watercontact angle on surface to 90 100 N.D. *1 which waterrepellency-imparting agent is applied (°) Water contact angle on surfaceto N.D. *1 100 N.D. *1 which water repellency-imparting agent is notapplied (°) Water repellency angle on surface to 30 10 80 which waterrepellency-imparting agent is applied (°) Water repellency angle onsurface to N.D. 10 80 which water repellency-imparting agent is notapplied (°) Water absorption rate of surface to 50 60 sec.≤ Instant*2which water repellency-imparting agent is applied (sec.) Waterabsorption rate of surface to Instant*2 60 sec.≤ Instant*2 which waterrepellency-imparting agent is not applied (sec.) Bending resistance (mm)40 65 50 Seepage test Suitability for inner Very good Very poor Verypoor clothing Suitability for outer Very good — — clothing Usage testNumber of times  0 2  2 seepage occurred (times) Result of sweatstaining Sweat staining of Dampness and When looking at the back of polosweating. Sweat in daytime, round shirt was flowed down on sweat stainwas prevented. the back and left a formed on the stain below. back.Overall evaluation   5.0 2.0   2.0 (points) Wearing comfort   5.0 1.5  3.5 (points) *1: The liquid drop used in determination was instantlyabsorbed, and thus determination was impossible. *2The water absorptionrate was too fast to be determined, and thus determination wasimpossible.

As shown in Tables 3 and 4, in the fiber article of Example 4, which wasa water repellency-imparted fiber article in which the waterrepellency-imparting agent was applied to the entire surface on one sidethereof, the surface to which the water repellency-imparting agent wasapplied (surface of the water-repellent region) had a water contactangle of 80 degrees or greater (water repellency angle of 40 degrees orless) and a water absorption rate of 10 seconds or greater, and also,the surface of the fiber article to which the water repellency-impartingagent was not applied and which was located on the opposite side to thesurface to which the water repellency-imparting agent was appliedexhibited high water absorbency such that the water contact anglethereon was 60 degrees or less, or such that the water repellency anglethereon was 50 degrees or greater, or such that the contact angle wasnot able to be measured. Thus, it can be determined that the fiberarticle of Example 4 had a water absorbing layer maintaining the “waterabsorbency in terms of a water absorption time of 30 seconds or less asmeasured in accordance with the dropping method of JIS L-1907”, thewater absorbing layer being located on the side that was closer to theskin of the user than the non-skin-side water-repellent region includingthe portion to which the water repellency-imparting agent was attached.Therefore, the fiber article of Example 4 exhibited the excellent effectof preventing bodily fluid seepage, compared with Comparative Examples 5and 6. Also, from the favorable results of the usage test, it can beseen that the fiber article of Example 4 can be effective in addressingsweat staining when actually used for an inner shirt. Furthermore, eventhough the fiber article of Example 4 had water-repellency, this fiberarticle had high air permeance and was less likely to cause dampness,compared with Comparative Example 5, which was the fiber article thathad water-repellency as well. Also, the results of the tactile feel testof Example 4 were equal to or better than those of Comparative Example6, which was the fiber article that was not made water-repellent. It istherefore clear that, according to the present invention exemplified byExample 4, bodily fluid seepage, specifically, sweat staining can beeffectively prevented without impairing the texture of the fiberarticle.

Although the test results shown in Tables 3 and 4 were obtained in thecase where the water repellency-imparting agent was applied to the innershirts (inner clothing), the effect of preventing sweat staining similarto that in the case where the water repellency-imparting agent wasapplied to the inner shirts can also be obtained in the case where thewater repellency-imparting agent is applied to, instead of the innershirts, a polo shirt (outer clothing) that is worn on an inner shirt, inparticular, in the case where the water repellency-imparting agent isapplied to the skin-facing surface (inner surface) side of that poloshirt.

INDUSTRIAL APPLICABILITY

According to the present invention, a water repellency-imparted fiberarticle is provided which can effectively prevent a bodily fluidexcreted from the body from seeping into clothing and thus becomingexternally visible.

The water repellency-imparted fiber article of the present inventionbasically has a simple configuration in which a waterrepellency-imparting agent is just attached to a fiber article, which isthe base of the water repellency-imparted fiber article, and theappearance and the basic performance of the water repellency-impartedfiber article are substantially unchanged from those intrinsic to thefiber article. Therefore, even though a measure to prevent bodily fluidseepage is taken in the water repellency-imparted fiber article of thepresent invention, this is not noticed by other people. Moreover, thewater repellency-imparted fiber article also exhibits excellent texture,usage feel, and the like as a fiber article.

1. A water repellency-imparted fiber article, comprising: a fiberarticle having a skin-facing surface to be disposed on a side that isrelatively close to the skin of a user during use and a non-skin-facingsurface to be disposed on a side that is relatively away from the skinof the user, the fiber article containing a water-absorbent fiber andhaving water absorbency in terms of a water absorption time of 30seconds or less as measured in accordance with the dropping method ofJIS L-1907; and a water repellency-imparting agent attached to the fiberarticle, wherein the water repellency-imparted fiber article has anon-skin-side water-repellent region on the non-skin-facing surface ofthe fiber article, the non-skin-side water-repellent region including aportion to which the water repellency-imparting agent is attached, thewater repellency-imparted fiber article has a water absorbing layer in asection of the fiber article that overlaps the non-skin-sidewater-repellent region in a plan view and on a side that is closer tothe skin of the user than the non-skin-side water-repellent region, thewater absorbing layer maintaining the water absorbency, and a surface ofthe non-skin-side water-repellent region has a water contact angle of 80degrees or greater and a water absorption rate of 10 seconds or greater.2. The water repellency-imparted fiber article according to claim 1,wherein both a portion to which the water repellency-imparting agent isattached and a portion to which the water repellency-imparting agent isnot attached are present in the non-skin-side water-repellent region. 3.The water repellency-imparted fiber article according to claim 1,wherein in a 50-mm-square region arbitrarily selected from thenon-skin-side water-repellent region, a percentage of the total area ofa portion to which the water repellency-imparting agent is attached tothe whole area of the 50-mm-square region is from 10% to 80%.
 4. Thewater repellency-imparted fiber article according to claim 1, wherein athickness of a portion to which the water repellency-imparting agent isattached, of the non-skin-side water-repellent region is from 5% to 60%of a thickness of the fiber article.
 5. The water repellency-impartedfiber article according to claim 1, wherein a bending resistance of asection where the non-skin-side water-repellent region is formed is 60mm or less, and is equal to or lower than the bending resistance of asection of the water repellency-imparted fiber article where thenon-skin-side water-repellent region is not formed, which is awater-repellent region non-formed portion.
 6. A waterrepellency-imparted fiber article, comprising: a fiber article having askin-facing surface to be disposed on a side that is relatively close tothe skin of a user during use and a non-skin-facing surface to bedisposed on a side that is relatively away from the skin of the user,the fiber article containing a water-absorbent fiber and having waterabsorbency in terms of a water absorption time of 30 seconds or less asmeasured in accordance with the dropping method of JIS L-1907, and awater repellency-imparting agent attached to the fiber article, whereinthe fiber article is underpants, the water repellency-imparted fiberarticle has a non-skin-side water-repellent region on thenon-skin-facing surface of the fiber article, the non-skin-sidewater-repellent region including a portion to which the waterrepellency-imparting agent is attached, the water repellency-impartedfiber article has a water absorbing layer in a section of the fiberarticle that overlaps the non-skin-side water-repellent region in a planview and on a side that is closer to the skin of the user than thenon-skin-side water-repellent region, the water absorbing layermaintaining the water absorbency, a surface of the non-skin-sidewater-repellent region has a water contact angle of 80 degrees orgreater and a water absorption rate of 10 seconds or greater a thicknessof a portion to which the water repellency-imparting agent is attached,of the non-skin-side water-repellent region is from 5% to 60% of athickness of the fiber article, and a bending resistance of a sectionwhere the non-skin-side water-repellent region is formed is 60 mm orless, and is equal to or lower than the bending resistance of a sectionof the water repellency-imparted fiber article where the non-skin-sidewater-repellent region is not formed, which is a water-repellent regionnon-formed portion.
 7. The water repellency-imparted fiber articleaccording to claim 1, wherein an amount of the waterrepellency-imparting agent attached decreases from the non-skin-facingsurface of the fiber article toward the skin-facing surface thereof. 8.The water repellency-imparted fiber article according to claim 1,wherein the water repellency-imparted fiber article has a skin-sidewater-repellent region on the skin-facing surface of the fiber article,the skin-side water-repellent region including a portion to which thewater repellency-imparting agent is attached, and an amount of the waterrepellency-imparting agent attached in the skin-side water-repellentregion is smaller than that in the non-skin-side water-repellent region.9. The water repellency-imparted fiber article according to claim 1,wherein the non-skin-facing surface of the fiber article has an unevenstructure, and the water repellency-imparting agent that forms thenon-skin-side water-repellent region is attached to projectionsconstituting the uneven structure.
 10. The water repellency-impartedfiber article according to claim 1, wherein, 10 mL or less of urine isabsorbed on the water absorbing layer is suppressed from transferring tothe non-skin-facing surface of water repellency-imparted fiber article.11. The water repellency-imparted fiber article according to claim 1,wherein the water repellency-imparting agent is a composition containinga modified silicone.
 12. The water repellency-imparted fiber articleaccording to claim 1, wherein, when the water repellency-imparted fiberarticle is washed by immersing the water repellency-imparted fiberarticle in a liquid containing 0.1 mass % of a commonly availabledetergent for clothing and ion exchanged water under stirring at arotational speed of 350 rpm for 10 minutes, and then lightly squeezingthe water repellency-imparted fiber article, and further immersing thewater repellency-imparted fiber article in ion exchanged water understirring at a rotational speed of 350 rpm for 10 minutes, an amount ofthe water repellency-imparting agent contained in the waterrepellency-imparted fiber article after washing is 20 mass % or lessbased on that before washing.
 13. A method for producing the waterrepellency-imparted fiber article according to claim 1, the methodcomprising: applying a water repellency-imparting agent to anon-skin-facing surface of a fiber article having water absorbency interms of a water absorption time of 30 seconds or less as measured inaccordance with the dropping method of JIS L-1907.
 14. The method forproducing the water repellency-imparted fiber article according to claim13, wherein after the water repellency-imparting agent is applied to thefiber article, the fiber article is dried under a condition that atemperature of the water repellency-imparting agent is 50° C. or less.15. The method for producing the water repellency-imparted fiber articleaccording to claim 13, wherein the application of the waterrepellency-imparting agent to the fiber article is performed by sprayingthe water repellency-imparting agent.
 16. The method for producing thefiber article according to claim 13, wherein the application of thewater repellency-imparting agent to the fiber article is performed byspraying the water repellency-imparting agent with a pump spray-typeapplication means in which the water repellency-imparting agent is putinto a container equipped with a sprayer. 17-29. (canceled)